Courses
Courses for Kids
Free study material
Offline Centres
More
Store Icon
Store

NCERT Exemplar for Class 7 Maths Solutions Chapter 2 Fractions & Decimals

ffImage
banner

Class 7 Maths NCERT Exemplar Solutions Chapter 2 Fractions & Decimals

Free PDF download of NCERT Exemplar for Class 7 Maths Chapter - 2 Fractions & Decimals solved by expert Maths teachers on Vedantu.com as per NCERT (CBSE) Book guidelines. All Chapter - 2 Fractions & Decimals exercise questions with solutions to help you to revise complete syllabus and score more marks in your examinations.

Every NCERT Solution is provided to make the study simple and interesting on Vedantu. Subjects like Science, Maths, English will become easy to study if you have access to NCERT Solution for Class 7 Science , Maths solutions and solutions of other subjects. You can also download NCERT Solutions for Class 7 Maths to help you to revise complete syllabus and score more marks in your examinations.

Courses

Access NCERT Exemplar Solutions for Class 7 Mathematics Chapter 2 - Fractions and decimals (Examples, Easy Methods and Step by Step Solutions)

Solved Examples

1. Savita is dividing 134kg of sweets equally among her seven friends. How much does each friend receive?

(a) 34kg

(b) 14kg

(c) 12kg

(d) 328kg

Ans: Correct answer is (b)

The given number of sweets is in mixed fraction form. We will first convert it. Hence 134=74

Now according to the given condition, Savita has to divide 74Kg sweets equally among her 7 friends.

Hence, the portion of sweet one person will get  = 74÷7=14kg

So, the amount of sweet each person will get is 14kg.


2. If 34 of a number is 12,the number is

(a) 9

(b) 16

(c) 18

(d) 32

Ans: Correct answer is (b)

The number is 16 as 34 of 16=34×16=12


3. Product of fractions 27 and 59 is

(a) 2×57+9

(b) 2+52+9

(c) 2×95×7

(d) 2×57×9

Ans: Correct answer is (d)

The product of fraction is 2×57×9


4 Given that 0<p<q<r<s and p,q,r,s are integers, which of the following is the smallest?

(a) p+qr+s

(b) p+sq+r

(c) q+sp+r

(d) r+sp+q

Ans: Correct answer is (a)

s and r are the largest and the second largest

p and q are the smallest and the second smallest

Smallest fraction =(p+q)(r+s)

So, the smallest fraction from the given option is p+qr+s


5. The next number of the pattern 60,30,15, is

(a) 10

(b) 5

(c) 154

(d) 152

Ans: Correct answer is (d)

602=30 and 302=15

The next number of the pattern is 152.


6. The decimal expression for 8 rupees 8 paise (in Rupees) is

(a) 8.8

(b) 8.08

(c) 8.008

(d) 88.0

Ans: Correct answer is (b)

We know, 100paise=1 rupee

Also, 8 paise =8100=0.08

Thus, Decimal expansion in rupees is (8+0.08)=8.08


7. Each side of a regular hexagon is 3.5cm long. The perimeter of the given polygon is

(a) 17.5cm

(b) 21cm

(c) 18.3cm

(d) 20cm

Ans: Correct answer is (b)

The side of a hexagon =3.5cm

Total number of sides in a Hexagon =6

The perimeter of hexagon = sum of all six sides =6×3.5=21cm

Therefore, the perimeter of the given polygon is 21cm.


8. 2.5÷1000 is equal to

(a) 0.025

(b) 0.0025

(c) 0.2500

(d) 25000

Ans: Correct answer is (b)

The division of 2.5÷1000is 0.0025


9. Which of the following has the smallest value?

(a) 0.0002

(b) 21000

(c) (0.2)22

(d) 2100÷0.01

Ans: Correct answer is (a)

The smallest value is 0.0002 because 21000=0.002, (0.2)22=0.042=0.02 and 2100÷0.01=2.


10. Which of the following has the largest value?

(a) 320.05

(b) 0.32050

(c) 3.20.05

(d) 3.250

Ans: Correct answer is (a)

The division of 320.05=640

So, the largest number is 320.05

0.32050=0.0064

3.20.05=64

3.250=0.064


11: The largest of the following is

(a) 0.0001

(b) 11000

(c) (0.100)2

(d) 110÷0.1

Ans: Correct answer is (d).

By division 110÷0.1=1

The largest value is 110÷0.1

 11000=0.001

(0.100)2=0.01


In Examples 12 to 19, fill in the blanks to make the statement true.

12: A fraction acts as an operator_____

Ans: The given true statement is:

A fraction acts as an operator of represents multiplication


13. Fraction which is reciprocal of 23 is_____

Ans: The given true statement is:

Fraction which is reciprocal of 23 is 32


14. Product of a proper and improper fraction is____ the improper fraction.

Ans: The given true statement is: 

Product of a proper and improper fraction is less than the improper fraction 


15. The two non-zero fractions whose product is 1, are called the____ of each other.

Ans: The given true statement is: 

The two non-zero fractions whose product is 1, are called the reciprocal of each other 


16: 5 rupees 5 paise =Rs?

Ans: 1paisa is 0.01rupees

So 5 rupees 5 paise =5.05rupees


17. 45mm=___m. 

Ans: 1 mm=0.001m

45mm=0.045m


18. 2.4×1000=

Ans: By multiplying 2.4×1000=2400


19. To divide a decimal number by 100, we shift the decimal point in the number to the ____by____ places. 

Ans: The given true statement is :

To divide a decimal number by 100, we shift the decimal point in the number to the left  by two  places.


In Examples 20 to 23 state whether the statements are True or False.

20: Reciprocal of an improper fraction is an improper fraction.

Ans: The given statement is False

The true statement is Reciprocal of an improper fraction is a proper fraction.


21: 225÷215=2

Ans: The given fraction is False

 The fraction of 225÷215=125×511=1211


22. 0.04÷0.2=0.2

Ans: The given division is True.

0.04÷0.2=0.2


23. 0.2×0.3=0.6

Ans: The given statement is False. 

By multiplying the values we get 0.2×0.3=0.06


24. Find 23 of 6 using circles with shaded parts.


seo images

Ans: From the following figure, try to find out 23 of 6 .

There are 12 shaded parts out of 18 parts which means 4 wholes. 

Thus 23 of 6 is 4


25. Find the value of 1427+131113+1(59)

Ans: Given expression = 1(307)+1(5013)+1(59)

=730+1350+95

=35150+39150+270150

=35+39+270150

=17275


26. There is a 3×3×3 cube which consists of twenty seven 1×1×1 cubes (see Fig. 2.3). It is 'tunneled' by removing cubes from the coloured squares.


seo images

Find:

(i) Fraction of number of small cubes removed to the number of small cubes left in a given cube.

Ans: Number of small cubes removed =1+1+1+1+1+1+ 1=7

So, required fraction =720


(ii) Fraction of the number of small cubes removed to the total number of small cubes.

Ans: The Required fraction =727


(iii) What part is (ii) of (i)?

Ans: Required part is 727÷720=727×207=2027


27. Ramu finishes 13 part of a work in 1 hour. How much part of the work will be finished in 215 hours?

Ans: The part of the work finished by Ramu in 1 hour =13

So, the part of the work finished by Ramu in 215 hours =215×13=115×13

=11×15×3=1115

Ramu will finish 1115 part of the work in 215 hours.


28. How many 23kg pieces can be cut from a cake of weight 4kg ?

Ans: The following figure represents 4 cakes each of 1kg and we need pieces of 23 kg.


seo images


In the above figure 

That is, 4÷23=4×32=6


29. Harmeet purchased 3.5kg of potatoes at the rate of ₹ 13.75per kg. How much money should she pay in nearest rupees?

Ans: Cost of 1kg potatoes =13.75.

Cost of 3.5kg potatoes =13.75×3.5

By multiplying 

13.75×3.5=48.125

Hence, cost of 3.5kg potatoes =Rs 48, to the nearest rupees.


30. Kavita had a piece of rope of length 9.5m. She needed some small pieces of rope of length 1.9m each. How many pieces of the required length will she get out of this rope?

Ans: Given 

The length of the rope =9.5m

The length of a small piece of rope =1.9m

Number of small pieces =9.5m÷1.9m

=9.51.9=9.5×101.9×10

=9519=5

So, she will get 5 small pieces of rope.


31. Three boys earned a total of ₹235.50. What was the average amount earned per boy?

Ans: Three boys earned =Rs235.50

The average amount earned per boy =Rs235.503

By division

The average amount earned per boy is ₹78.50


32. Find the product of

(i) 12 and 58

Ans: The product of 12×58=1×52×8=516


(ii) 13 and 75

Ans: The product of 13×75=1×73×5=715


(iii) 43 and 52

Ans: The product of  43×52=4×53×2=206=103


33. Observe the 3 products given in Example 32 and now give the answers of the following questions.

(i) Does interchanging the fractions in the example, 12×58, affect the answer?

Ans: By interchanging 12×58 we get 58×12

58×12=5×18×2=516 which is same as the product we get

in Example 32 by multiplying 12 and 58. This means that interchanging the fractions does not affect the answer.


(ii) Is the value of the fraction in the product greater or less than the value of either fraction?

Ans: By observing the 3 products given in the solution of Example 32, we come to know that the value of the fractions in the products are as follows

(a) The product of two fractions whose value is less than 1 so, the product fractions is less than each of the fractions that are multiplied.

(b) The product of a proper and an improper fraction is less than the improper fractions and greater than the proper fraction.

(c) The product of two improper fractions is greater than each of the two fractions.


34. Reshma uses 34m of cloth to stitch a shirt. How many shirts can she make with 214m cloth?

Ans: Length of cloth needed to stitch 1 shirt =34m

Length of cloth she has =214=94m

No. of shirts she can make by 94m cloth =94÷34 shirts =94×43 shirts =3 shirts

Hence, she can make 3 shirts using 214m of cloth.


35: If the fraction of the frequencies of two notes have a common factor between the numerator and denominator, the two notes are harmonious. Use the graphic below to find the fraction of frequency of notes D and B.


seo images

Ans: Fraction of frequencies of notes D and B is 

= Frequency of note D Frequency of note B=297495=3×3×3×113×3×5×11

So, the fraction of the frequencies of notes D and B is 35

Clearly, the notes D and B are harmonies. 


36. Khilona said that we have gone about 120km or 23 of the way to the campsite. So, how much farther do we have to go? 

Ans: Let total distance be x km.

According to question,

23 of x=120 

x=180 km


Exercise

1. 25×515 is equal to:

(a) 2625

(b) 5225

(c) 25

(d) 6

Ans: Option (b) is correct

Given that,

25×515

Converting mixed fraction into the whole fraction

25×265=5225


2. 334÷34is equal to:

(a)3

(b) 4

(c) 5

(d) 4516

Ans: Option (c) is correct.

Converting mixed fraction into the whole fraction

154÷34

Converting divide into multiplication so we reciprocal the fraction 34

154×43=5


3. A ribbon of length 514m is cut into small pieces each of length 34m. Number of pieces will be:

(a) 5

(b) 6

(c) 7

(d) 8

Ans: Option (c) is correct.

Convert the mixed fraction

The length of ribbon =514=214m

Length of each small piece =34m

No. of pieces =214÷34

No. of pieces =214×43=7


4. The ascending arrangement of 23,67,1321 is:

(a) 67,23,1321

(b) 1321,23,67

(c) 67,1321,23

(d) 23,67,1321

Ans: Option (b) is correct.

The given numbers are 23,67,1321

21 is the LCM of denominators (3,7,21)

23=2×73×7=1421;67=6×37×3=1821;1321=13×121×1=1321

Now 13<14<18.

1321<1421<18211321<23<67

Hence, the ascending arrangement is

1321,23,67


5. Reciprocal of the fraction 23 is:

(a) 2

(b) 3

(c) 23

(d) 32

Ans: Option (d) is correct.

Reciprocal of the asked fraction is 1÷23=32


6. The product of 1113 and 4 is:

(a) 3513.

(b) 5313

(c) 1335

(d) 1353

Ans: Option (a) is correct.

The product of 1113×4=4413

 =3513


7. The product of 3 and 425 is.:

(a) 1725

(b) 245

(c) 1315

(d) 5113

Ans: Option (c) is correct.

First, we have to convert the mixed fraction into improper fraction 425=225

3×425=3×225=665

=1315


8. Pictorial representation of 3×23 is:


seo images

Ans: Option (b) is correct.

3×23=23+23+23

Therefore, pictorial representation is


seo images


9. 15÷45 equal to:

(a) 45

(b) 15

(c) 54

(d) 14

Ans: Option (d) is correct.

By division 15÷45=15×54

=14


10. The product of 0.03×0.9 is:

(a) 2.7

(b) 0.27

(c) 0.027

(d) 0.0027

Ans: Option (c) is correct.

The product of  0.03×0.9

=3100×910

=271000=0.027


11. 57÷6 is equal to:

(a) 307

(b) 542

(c) 3042

(d) 67

Ans: Option (b) is correct.

By division 57÷6

=57×16=542


12. 516÷92 is equal to:

(a) 316

(b) 127

(c) 5127

(d) 3127

Ans: Option (d) is correct.

By division 516÷92

=316÷92=316×29

=3127


13. Which of the following represents 13 of 16 ?

(a) 13+16

(b) 1316

(c) 13×16

(d) 13÷16

Ans: Option (c) is correct.

13 of 16=13×16


14. 37 of 25 is equal to

(a) 512

(b) 535

(c) 135

(d) 635

Ans: Option (d) is correct.

37 of 25=37×25=635


15. One packet of biscuits requires 212 cups of flour and 123 cups of sugar. Estimated total quantity of both ingredients used in 10 such packets of biscuits will be

(a) less than 30 cups

(b) between 30 cups and 40cups

(c) between 40 cups and 50 cups

(d) above 50 cups

Ans: Option (c) is correct.

The requirement of sugar and flour for one packet of biscuits =(212+123)

=(52+53)=(15+106)=256 cups 

Therefore, the requirement of both ingredients for 10 packets

=10×256=1253=4123 cups 

Total estimated quantity will lie between 40and 50 cups.


16. The product of 7 and 634 is

(a) 4214

(b) 4714

(c) 4234

(d) 4734

Ans: Option (b) is correct.

The product of  7×634

=71×274=1894

=4714


17. On dividing 7 by 25, the result is

(a) 142

(b) 354

(c) 145

(d) 352

Ans: Option (d) is correct.

By dividing,

7÷25=7×52=352


18. 223÷5 is equal to

(a) 815

(b) 403

(c) 405

(d) 83

Ans: Option (a) is correct.

First, we have to convert the mixed fraction into improper fraction 223=83 

Then

223÷51

=83×15=815


19. 45 of 5kg apples were used on Monday. The next day 13 of what was left was used. Weight (in kg ) of apples left now is

(a) 27

(b) 114

(c) 23

(d) 421

Ans: Option (c) is correct.

The weight of apple used on Monday =45×5=4Kg

Weight of apples left on next day =(54)=1kg

Weight of apples used on next day 13 of 1kg=13

Therefore, weight of apples left =(113)=23kg


20. The picture 


seo images

Interprets

(a) 14÷3

(b) 3×14

(c) 34×3

(d) 3÷14

Ans: Option (b) is correct.

14+14+14=34


In Questions 21 to 44, fill in the blanks to make the statements true.

21. Rani 27 ate part of a cake while her brother Ravi ate 45 of the remaining. Part of the cake left is _____

Ans: Let, there is only one cake,

Now the part of the cake ate by the Rani was 27 

Hence, the cake left

127=57

Now the part of the cake ate by the Ravi was

45×57=47

Therefore, the cake left

5747=17


22. The reciprocal of 37 is______

Ans: The reciprocal of 37 is 73


23. 23 of 27 is_____

Ans: The multiply of 23×27

=2×9=18


24. 45 of 45 is____

Ans: The multiply of 45×45

=4×9=36


25. 4×613 is equal to______

Ans: The product of 4×613

=4×193=763

=2513


26. 12 of 427 is_____

Ans:  First we have to convert the mixed fraction into improper fraction 427=307

12 of 427

=12×307

=157=217


27. 19 of 65 is________

Ans: The product the 19 of 65

=19×65

=645=215


28. The lowest form of the product 237×79 is______

Ans: The lowest form of 237×79

=177×79

=179=189


29. 45÷4 is equal to_____

Ans: By division 45÷4

=45×14=15

30. 25 of 25 is____

Ans: The product is 25 of 25

=25×25

=2×5=10

31. 15÷56=15__65 

Ans: While dividing one fraction by another fraction, we multiply the first fraction by the reciprocal of the other.

15÷56=15×65


32. 3.2×10=

Ans: To multiply a decimal number by 10, we move the decimal point in the number to the right by as many places as many zeros (0) are at the right of one

3.2×10=32


33. 25.4×1000=

Ans: To multiply a decimal number by 1000 we move the decimal point in the number to the right by as many places as many zeros (0) are at the right of one.

25.4×1000=25400


34. 93.5×100=

Ans: To multiply a decimal number by 100 we move the decimal point in the number to the right by as many places as many zeros (0) are at the right of one 

93.5×100=9350


35. 4.7÷10=

Ans: To divide a decimal number by 10, shift the decimal point in the decimal number to the left by as many places as there are zeros over 1, to get the quotient.

4.7÷10=0.47


36. 4.7÷100=

Ans: To divide a decimal number by 100, shift the decimal point in the decimal number to the left by as many places as there are zeros over 1, to get the quotient.

4.7÷100=0.047


37. 4.7÷1000=

Ans: To divide a decimal number by 1000, shift the decimal point in the decimal number to

the left by as many places as there are zeros over 1, to get the quotient.

4.7÷1000=0.0047


38. The product of two proper fractions is______than each of the fractions that are multiplied.

Ans: The product of two proper fractions is less than each of the fractions that are multiplied.


39. While dividing a fraction by another fraction, we _________ the first fraction by the _______ of the other fraction.

Ans: While dividing a fraction by another fraction, we multiply the first fraction by the reciprocal of the other fraction.


40. 8.4÷___=2.1 

Ans: 8.4÷4=2.1

Let us assume the missing fraction be x,

Then,

8.4÷x=2.1

8.4/x=2.1

By cross multiplication, we get,

x=8.4/2.1

x=84/21

x=28/7

x=4


41. 52.7÷____=0.527

Ans: Let consider x be the missing variable

 52.7÷x=0.527

x=52.70.527=100

x=100


42. 0.5___0.7=0.35

Ans: Let determine the exponent 

0.5of0.7=0.35

So, 0.5×0.7=0.35


43. 2___53=103

Ans: The missing exponent is 

  2×53=103

  =2×53=103


44. 2.001÷0.003=

Ans: By division

   2.001÷0.003=

   =20011000×10003

   =667


In each of the Questions 45 to 54, state whether the statement is True or False.

45. The reciprocal of a proper fraction is a proper fraction.

Ans: The given statement is False, 

So, the correct statement is the reciprocal of a proper fraction is an improper fraction.


46. The reciprocal of an improper fraction is an improper fraction.

Ans: The given statement is False, 

So, the correct statement is the reciprocal of an improper fraction is a proper fraction.


47. Product of two fractions =  Product of their denominators  Product of their numerators 

Ans: The given statement is false. 

The correct statement is Productoftwofractions= Product of their numerators  Product of their denominators 


48. The product of two improper fractions is less than both the fractions.

Ans: The given statement is False,

Correct statement is the product of two improper fractions is greater than both the fractions.


49. A reciprocal of a fraction is obtained by inverting it upside down.

Ans: The given statement is True


50. To multiply a decimal number by 1000 , we move the decimal point in the number to the right by three places.

Ans: The given statement is True


51. To divide a decimal number by 100 , we move the decimal point in the number to the left by two places. 

Ans: The given statement is True


52. 1 is the only number which is its own reciprocal

Ans: The given statement is True


53. 23 of 8 is same as 23÷8

Ans: The given statement is False

The product of 23×8=163

And

The division of  23÷8=23×18=112

23 of 823÷8


54. The reciprocal of 47 is 47

Ans: The given statement is False, 

The reciprocal of 47 is 74


55. If 5 is added to both the numerator and the denominator of the fraction 59, will the value of the fraction be changed? If so, will the value increase or decrease?

Ans: Given, 59 and 5+59+5=1014=57

Here, 5957

Now, 59<57

Therefore, the value is increased.


56. What happens to the value of a fraction if the denominator of the fraction is decreased while the numerator is kept unchanged?

Ans: If the denominator of the fraction is decreased, the value of a fraction is increased while the numerator remains unchanged.


57. Which letter comes 25 of the way among A andJ?

Ans: The total letter in number between A and J is 10.

Then, 25×10=4

Therefore, D comes at 410.


58. If 23 of a number is 10, then what is 1.75 times of that number?

Ans: Let x be the number

23×x=10

23×x=10

x=10÷23=10×32

x=5×3=15

Now, 1.75×x=1.75×15=26.25


59. In a class of 40 students, 15 of the total number of students like to eat rice only, 25 of the total numbers of students like to eat chapati only and the remaining students like to eat both. What fractions of the total number of students like to eat both?

Ans: Given,

Total number of students is 40

Number student who eats rice only =15×40=8

Number student who eats chapati only =25×40=16

Number of students who eats both =40(8+16)=16

Therefore, the required fraction =1640=25


60. Renu completed 23 part of her homework in 2 hours. How much part of her homework had she completed in 114 hours?

Ans: Let total homework denoted as x

Renu completed the part of homework in 2 hours =23x

Thus, completed work by her in an hour

 =23x×12

 =x3

Therefore, the part of completed in 114 hours

x3×114=x3×54

=5x12


61. Reemu read 15 th pages of a book. If she reads further 40 pages, she would have read 710 th pages of the book. How many pages are left to be read? 

Ans: The total page inside the book be x and number of pages read by Reemu =x5+40=7x10 

7x10x5=40 

[(72)10]x=40

 510x=40

 x=40×105=80

Now, number of pages read by Reemu =710×80=56 

Therefore, number of pages remains to be read =(8056)=24


62. Write the number in the box such that

37×___=1598

Ans: Let number in the box be y

37×y=1598

y=1598÷37

y=1598×73=514

Therefore, the required number is 514.


63. Will be quotient 716÷323 be a fraction greater than 1.5 or less than1.5? Explain.

Ans: The quotient of 

716÷323=436÷113

=436×311=4322

=1.95

Therefore, 716÷323 fraction is greater than 1.5.


64. Describe two methods to compare 1317 and 0.82. Which do you think is easier and why?

Ans: Method-I: Conversion of both numbers 1317 and 0.82

1317=0.76 and 0.82

Method-II: Change into fraction

0.82=82100=4150 and 1317

Hence, the method of converting numbers into decimals is easy.


65. Health: the directions for a pain reliever recommend that an adult of 60 kg and over take 4tablets every 4 hours as needed, and an adult who weighs between 40 and 50kg take only 212 tablets every 4 hours as needed. Each tablet weighs 425 grams.

(a) If a 72kg adult takes 4 tablets, how many grams of pain reliever is he or she receiving?

Ans:  Each tablets of 425 grams

Then, weight of 4 tablets =4×425=1625grams


(b) How many grams of pain reliever is the recommended dose for an adult weighing 46kg ?

Ans: An adult of who has weight of 46 takes 212Tablets

Hence, weight of 212 Tablets

425×212 gram

=425×52=25 grams


66. Animals: The label on a bottle of pet vitamins lists dosage guidelines. What dosage would you give to each of these animals?

Do Good Pet Vitamins 

• Adult dogs: 12 tsp (tea spoon full) per 9kg body weight 

• Puppies, pregnant dogs, or nursing dogs: 12 tsp per 4.5kg body weight 

• Cats: 14 tsp per 1kg body weight

(a) A 18kg adult dog

Ans: Dosage given to a 18kg adult dog

=(12+12)=1tsp


(b) A 6kg cat

Ans: Total dosages are given to a cat of weight 6 kg

=6×14=112tsp


(c) A 18kg pregnant dog

Ans: Dosages are given to a pregnant dog weighing 18kg

 =12×14.5×18

 =9×1045=2tsp


67. How many 116 kg boxes of chocolates can be made with 112kg chocolates?

Ans: 1 box filled with 116kg of chocolates.

Hence, 1kg chocolates to be filled in 1÷116 =1×16=16 boxes

Now, 112Kg chocolates to be filled

16×112=16×32=24 boxes 


68. Anvi is making a bookmarker like the one shown in Fig. 2.6. How many bookmarks can she make from a 15m long ribbon?


seo images

Ans: Length of one bookmaker =1012=212cm

Avni can make the number of bookmaker, from the ribbon of size 15×100

=(121÷2×15×100)=221×1500

=300021=142.8142

Avni can make 142 bookmakers from a 15m long ribbon.


69. A rule for finding the approximate length of diagonal of a square is to multiply the length of a side of the square by 1.414. Find the length of the diagonal when:

(a) The length of a side of the square is 8.3cm.

Ans: The square side's length is 8.3cm

Diagonal length of the square

1.414×8.3=11.73611.74cm


(b) The length of a side of the square is exactly 7.875cm.

Ans: The square side's length is 7.875cm 

Diagonal length of the square

=1.414×7.875

=11.13511.14cm


70. The largest square that can be drawn in a circle has a side whose length is 0.707times the diameter of the circle. By this rule, find the length of the side of such a square when the diameter of the circle is

(a) 14.35cm

Ans: The Circle's diameter is 14.35cm.

Thus, the square side's length is =0.707×14.35

 =10.14545=10.15cm 


(b) 8.63cm

Ans: The Circle's diameter is 8.63cm.

Thus, the square side's length is =0.707×8.63 

=6.10141=6.10cm


71. To find the distance around a circular disc, multiply the diameter of the disc by 3.14. What is the distance around the disc when:

(a) the diameter is 18.7cm ?

Ans: Diameter of the disc is 18.7cm.

Thus, the distance around the disc =3.14×18.7

=58.718cm


(b) the radius is 6.45cm ?

Ans: Disc's radius is 6.45cm

Diameter of disc is 6.45×2=12.9cm

Thus, the distance around the disc is =3.14×12.9=40.506cm


72. What is the cost of 27.5m of cloth at 53.50 per meter?

Ans: Given cost of 1 meter of cloth is Rs 53.50

Thus, Cost of 27.5 meters of cloth is

(53.50×27.5)=Rs.1471.25


73. In a hurdle race, Nidhi is over hurdle B and 26 of the way through the race, as shown in Fig. 2.7.


seo images

Then, answer the following:

(a) Where will Nidhi be, when she is 46 on the way through the race?

Ans: Nidhi will be at hurdle D when she is 46 on the way through the race.


(b) Where will Nidhi be when she is 56 on the way through the race?

Ans: Nidhi will be at hurdle E when she is 56 on the way through the race.


(c) Give two fractions to tell what part of the race Nidhi has finished when she is over hurdle C.

Ans: When Nidhi will be at hurdle C, she would finished the 36 or 12 of the race.


74. Diameter of Earth is 12756000m. In 1996, a new planet was discovered whose diameter is of the diameter 586 of Earth. Find the diameter of this planet in km.

Ans: Given, diameter of the earth is 12756000m

 Diameter of a new planet earth

=586×12756000=741627.90m

741627.901000=741.6km


75. What is the product of 5129 and its reciprocal? 

Ans: The reciprocal of 5129 is 1295

Now, the product is

5129×1295=1


76. Simplify: 212+15212÷15

Ans: The simplification of the fraction 212+15212÷15=52+1552÷15

=2710×225

=27125


77. Simplify: 14+15138×35

Ans: The simplification of fraction

14+15138×35=14+151940

=5+42040940

=920×4031

=1831


78. Divide 310 by (14 of 35)

Ans: The division of fractions

310÷(14×35)=310÷320

=310×203=2


79. 18 of a number equals 25÷120. What is the number?

Ans: Let the number be x

18×x=25÷120

x8=25×201

x8=8

x=64

Therefore, the required number is 64.


80. Heena's father paid an electric bill of ₹ 385.70 out of a 500 rupee note. How much change should he have received?

Ans: The amount Heena's father has Rs 500

The amount spent in electricity bill Rs. 385.70

Therefore, the remaining money

Rs.(500385.70)=114.30


81. The normal body temperature is 98.6F. When Savitri was ill her temperature rose to 103.1F. How many degrees above normal was that?

Ans: Given data 

98.6F is the normal body temperature

103.1F was the body temperature of Savitri, when she was ill.

For the normal 

103.1F98.6F=4.5F


82. Meteorology: One measure of average global temperature shows how each year varies from a base measure. The table shows results for several years.

Year

1958

1964

1965

1978

2002

Difference from Base

0.10C

0.17C

0.10C

(150)C

0.54C

See the table and answer the following:

(a) Order the five years from coldest to warmest.

Ans: From coldest to warmest.

1964,1965,1978,1958,2002 were the orders of five years from coldest to warmest.


(b) In 1946 the average temperature varied by 0.03C from the base measure. Between which two years should 1946 fall when the years are ordered from coldest to warmest?

Ans: In 1946, The average temperature variation is 0.03C

Then 0.10C<0.03C<(150)C

Therefore, 1946 should lies between 1965and 1978


83. In her science class, Jyoti learned that the atomic weight of Helium is 4.0030. of Hydrogen is 1.0080 and of Oxygen is 16.0000. Find the difference between the atomic weights of:

(a) Oxygen and Hydrogen

Ans: Given,

Atomic weight of Hydrogen is 1.0080

Atomic weight of Helium is 4.0030

Atomic weight of Oxygen is 16.0000

The difference of weight of Oxygen and Hydrogen

=16.00001.0080=14.9920


(b) Oxygen and Helium

Ans: The difference of weight of Oxygen and Helium

=16.00004.0030=11.9970


(c) Helium and Hydrogen

Ans: The difference of weight of Helium and Hydrogen

4.00301.0080=2.9950


84. Measurements made in the science lab must be as accurate as possible. Ravi measured the length of an iron rod and said it was 19.34cm long; Kamal said 19.25cm; and Tabish said 19.27cm. The correct length was 19.33cm. How much error was made by each of the boys?

Ans: Iron rod's correct length is 19.33cm.

The length of rod measured by Kamal =19.25cm

Therefore, the error made by the Kamal

19.2519.33=0.08cm

The length of rod measured by Tabish =19.27cm

Therefore, the error made by Tabish

19.2719.33=0.06cm

The length of rod measured by Ravi =19.34cm

Therefore, the error made by the Ravi

19.3419.33=+0.01cm


85. When 0.02964 is divided by 0.004, what will be the quotient?

Ans: By division

0.029640.004=2964100000÷41000

=2964100000×10004

=741100

=7.41


86. What number divided by 520 gives the same quotient as 85 divided by 0.625?

Ans: Let number Y be 520

Y÷520=85÷0.625

y520=850.625

y=44200625×1000

=70.72×1000

=70720


87. A floor is 4.5m long and 3.6m wide. A6cm square tile costs23.25. What will be the cost to cover the floor with these tiles?

Ans: Length of floor is 4.5m×100=450cm

Width of the floor =3.6m=(3.6×100)=360cm

Hence, Area of the floor =360×450=162000cm2

Side of the square tile =6cm

Now, one square tile of cost =6×6=36cm2

Number of tiles required to cover the floor

= Area of floor  Area of onetile =1620036=4500

Now, the cost of one tile is Rs. 23.25

Therefore, the cost of 4500 tiles

23.25×4500= Rs.104625


88. Sunita and Rehana want to make dresses for their dolls. Sunita has 34m of cloth, and she gave 13 of it to Rehana. How much did Rehana have?

Ans: Sunita has the length of clothes =34m 

So, the Rehana's cloth length =13 of 34m=13×34

=14m


89. A flower garden is 22.50m long. Sheela wants to make a border along one side using bricks that are 0.25m long. How many bricks will be needed?

Ans: The garden has the length of =22.50m

Length of one brick =0.25m

So, the No. of brick requires making the border

= length of the garden  Length of one brick 

=22.500.25=225025=90


90. How much cloth will be used in making 6 shirts, if each required 214m of cloth, allowing 18m for waste in cutting and finishing in each shirt?

Ans: Length of cloth required for one shirt

=214m+18m=(94+18)

=(18+18)

=198m 

Hence, the length of cloth required for six shirts

=198×6=19×34m

=574

=1414m


91. A picture hall has seats for 820 persons. At a recent film show, one usher guessed it was 34 full, another that it was 23 full. The ticket office reported 648 sales. Which usher (first or second) made the better guess?

Ans: Total no. of seats =820

Total ticket's sale =648

The first usher guessed the number of sold tickets

=34×820=615

The second usher guessed the number of sold tickets 

=23×820=16403 

=546.66547

So, 615 is near to 648 than 547

So, the first usher guessed better.


92. For the celebrating children's students of Class VII bought sweets for Rs.740.25and cold drink for ₹ 70.If 35 students contributed equally what amount was contributed by each student?

Ans: The total amount spent on children day

=740.25+70=810.25

Number of students who made contribution =35

So, the contribution of each student =810.2535

=Rs.23.15


93. The time taken by Rohan in five different races to run a distance of 500m was 3.20minutes, 3.37minutes, 3.29minutes, 3.17 minutes and 3.32 minutes. Find the average time taken by him in the races.

Ans: Total number of races is 5.

In five races time taken by Rohan

 3.20+3.37+3.29+3.17+3.32 

=16.35

The average time taken by Rohan =16.355 

=3.27 minutes


94. A public sewer line is being installed along 8014m of road. The supervisor says that the laborers will be able to complete 7.5m in one day. How long will the project take to complete?


seo images

Ans: The sewer lines length =8014=3214m

Given 7.5m long sewer can made in one day

So, 3214 meter long sewer takes the time of

17.5×3214=3210300

=10.711 days 


95. The weight of an object on the moon is 16 its weight on Earth. If an object weighs 535kg on Earth, how much would it weigh on the moon?

Ans: Weight of the object on the earth =535=285kg 

So, weight of that particular object on the moon

=16×285=1415

=0.93kg


96. In a survey, 200 students were asked what influenced them most to buy their latest CD. The results are shown in the circle graph. 


seo images

(a) How many students said radio influenced them most?

Ans: From flow chart

The no. of students, influenced by radio 

920×200=90


(b) How many more students were influenced by radio than by a music video channel? 

Ans: The no. of students, influenced by music video channel

225×200=16


(c) How many said a friend or relative influenced them or they heard the CD in a shop?

Ans: The no. of students, influenced by relative or friend

320×200=30

The no. of students, influenced by seeing or hearing CD in shop

=110×200=20

Therefore, the total number of students who were influenced by both

 =30+20=50


97. In the morning, a milkman filled  512L of milk in his can. He sold to Renu, Kamla and Renuka 34L each; to Shadma he sold 78L; and to Jassi he gave 112L. How much milk is left in the can?

Ans: The container can contain the total quantity of milk

=512L=112L

The total quantity to be sold

=(34+34+34+78+112)

 =(18+7+128)=378L

Now, quantity of milk left in the milk can

=(112378)=44378

=78L


98. Anuradha can do a piece of work in 6 hours. What part of the work can she do in 1 hour, in 5 hours, in 6 hours?

Ans: X is the part of work done by Anuradha in 6 hours 

Then, work done in an hour =X6

The part of work done in 5 hours =56X

The part of work done in 6 hours =X6×6=X

So, Anuradha can do 16 part of work in 1 hour, 

56 part of work in 5 hours and 6 hours to be taken for complete work done.


99. What portion of a 'saree' can Rehana paint in 1 hour if it requires 5 hours to paint the whole saree? In 435 hours? In 312 hours?

Ans: Rehana painted, 1 portion of saree in 5 hours

Hence, the portion of saree painted by her in an hour =15

Then portion of saree painted by her in

435 hours =15×435=2325

The portion of saree painted by her

312 hours =15×312=710


100. Rama has 614kg of cotton wool for making pillows. If one pillow takes 114kg, how many pillows can she make?

Ans: Given, total quantity of cotton wool =614=254kg 

The wool required for 1 pillow

254÷54=254×45

 =5


101. It takes 213m of cloth to make a shirt. How many shirts can Radhika make from a piece of cloth 913m long?

Ans: Given, the length of cloth is 913 meter 

The length of shirt required to make a cloth =213=73m

Then required number of shirts

 =283÷73

=283×37

=4


102. Ravi can walk 313km in one hour. How long will it take him to walk to his office which is 10km from his home?

Ans: Time taken by him to walk 1km

(1÷313)=(1÷103) hours 

=(1×310)=310 hours 

So, time taken by Ravi to walk 10km 

=(10×310)=3 hours


103. Raj travels 360km on three fifths of his petrol tank. How far would he travel at the same rate with a full tank of petrol?

Ans: Raj travels 360km with 35 filled tank of petrol When tank is full with petrol the distance he travels

(360÷35)=360×53

=120×5

=600km 


104. Kajol has ₹$75. This is 38 of the amount she earned. How much did she earn?

Ans: Let Kajol earned x money

38×x=75

x=75×83

x=200

Kajol earned the amount of 200.


105. It takes 17 full specific types of trees to make one tonne of paper. If there are 221

 such trees in a forest, then 

(i) what fraction of forest will be used to make;

(a) 5 tonnes of paper.

Ans: The making of one tonne of paper requires 17 trees 

Total given number of trees is 221

Hence, fraction of forest will used to make one tones of paper 

=17221=113

 Fraction of forest will used to make 5 tons of paper 

=113×5=513


(b) 10 tonnes of paper.

Ans: Fraction of forest will used to make 10 tons of paper 

=113×10=1013


(ii) To save 713 part of the forest how much paper we have to save.

Ans: We have X tons of paper to save 713 part of forest

Fraction of forest will used to make X tons of paper 113×X=X13

Now,

X13=713

X=713×13=7


106. Simplify and write the result in decimal form :

(1÷29)+(1÷315)+(1÷223)

Ans: Given,

(1÷29)+(1÷315)+(1÷223)

=(1×92)+(1÷165)+(1÷83)

=92+516+38

=72+5+616

=8316=5.1875


107. Some pictures (a) to (f) are given below. Tell which of them show:

(1) 2×14

(2) 2×37

(3) 2×13

(4) 14×4

(5) 3×29

(6) 14×3

(a) 


seo images

(b) 


seo images

(c) 


seo images

(d) 


seo images

(e)


seo images

(f) 


seo images

Ans: 1. 2×14 represents:

i) Addition of 2 figures

ii) 1 shaded part out of 4 equal parts

iii) Represents by figure d


2. 2×37 represents:

i) Addition of 2 figures

ii) 3 shaded parts out of 7 equal parts

iii) Represents by figure f


3. 2×13 represents:

i) Addition of 2 figures

ii) 1 shaded part out of 3 equal parts

iii) Represents by figure c


4. 14×4 represents:

i) Addition of 4 figures

ii) 1 shaded part out of 4 equal parts

iii) Represents by figure b


5. 3×29 represents:

i) Addition of 3 figures

ii) 2 shaded part out of 9 equal parts

iii) Represents by figure a


6. 14×3 represents:

i) Addition of 3 figures

ii) 1 shaded part out of 4 equal parts

iii) Represents by figure d


108. Evaluate: (0.3)×(0.3)(0.2)×(0.2)

Ans: The decimal of (0.3)×(0.3)(0.2)×(0.2)

=310×310(210×210)

=91004100

=5100=0.05


109. Evaluate 0.60.3+0.160.4

Ans: The fraction of 0.60.3+0.160.4

=(610×103)+(16100×104)

=2+410=20+410

=2410=2.4


110. Find the value of: (0.2×0.14)+(0.5×0.91)(0.1×0.2)

Ans: The fraction is (0.2×0.14)+(0.5+0.91)(0.1×0.2)

=(210×14100)+(510×91100)(110×210)

=281000+45510002100

=241.510=24.15


111. A square and an equilateral triangle have a side in common. If side of triangle is 43cm long, find the perimeter of figure formed (Fig. 2.8).


seo images

Ans: Sides of the equilateral triangle =43cm Hence, square's side =43cm

Perimeter of the given figure =(43+43+43+43+43)

=5×43

=203

=623cm


112. Rita has bought a carpet of size 4m×623m. But her room size is 313m×513m. What fraction of area should be cut off to fit wall to wall carpet into the room?

Ans: The area of the carpet =4×623=803m2

Area of room =313×513

=103×163m2

=1609m2

Hence, area to be cut off =(8031609)m2

=809m2

 

113. Family photograph has length 1425cm and breadth 1025cm. It has border of uniform width 235cm. Find the area of the framed photograph.

Ans: Given data

Length of the photo =1425=725cm

Breadth of photo =1025=525cm

Length of framed photograph =(725+135+135)=985cm

Breadth of framed photograph =(525+135+135)=785cm

Hence, area of framed photograph =985×785

=764425

=3051925cm2


114. Cost of a burger is Rs 2034 and of Macduff is Rs 1512. Find the cost of 4 burgers and 14 mac puffs.

Ans: Cost of a burger =2034. =Rs834

Cost of a Mac Puffs =1512=Rs312

Hence, cost of 4 burgers =834×4=Rs.83

and cost of 14 Macduff's =312×14=Rs.217

Therefore, total cost =217+83=Rs.300 


115. A hill, 10113m in height, has 14 th of its height under water. What is the height of the hill visible above the water?

Ans: Height of the hill =10113m=3043m

Hill's height under water =14×3043=763m 

Therefore, hill visible above the water =(3043763)=2283=76m


116. Sports: Reaction time measures how quickly a runner reacts to the starter pistol. In the 100m dash at the 2004 Olympic Games, Lauryn Williams had a reaction time of 0.214 second. Her total race time, including reaction time, was 11.03 seconds. How long did it take her to run the actual distance?

Ans: The race time of Lauryn Williams =11.03 Seconds

Her reaction time =0.214 Seconds

Hence, time required to run the actual distance 

=(11.030.214)=10.816 Seconds


117. State whether the answer is greater than 1 or less than 1. Put a  mark in the appropriate box.

Questions

Greater than 1

Less than 1

23÷12



23÷21



6÷14



15÷12



413÷312



23×812



Ans: The answer is 

1. 23÷12=23×21=43>1

2. 23÷21=23×12=13<1

3. 6÷14=6×4=24>1

4. 15÷12=15×21=25<1

5. 413×312=133×27=2621>1

6. 23×812=23×172=173>1

Questions

Greater than 1

Less than 1

23÷12

yes


23÷21


yes

6÷14

yes


15÷12


yes

413÷312

yes


23×812

yes



118. There are four containers that are arranged in the ascending order of their heights. If the height of the smallest container given in the figure is expressed as 725x=10.5cm. Find the height of the largest container.


seo images

Ans: Given,

Height of the smaller container is 10.5cm

725x=10.5

 x=(10.5÷725)

=(10510×257)

=37510cm

So, the height of the largest container is 37.5cm.


In Questions 119 to 122, replace '?' with appropriate fraction

119. 

seo images

Ans: The given pattern, 78,

78×3=724,

724×3=772,

772×3=7216

Next fraction is 7216×3=7648


120

seo images

Ans: The given pattern,

  332

 332×2=316

 316×2=38,

 38×2=34 

So, Next fraction is 34×2=32


121

seo images

Ans: The given pattern

0.05,

0.05×10=0.5,

0.5×10=5,

5×10=50, 

So, Next fraction is 50×10=500


122

seo images

Ans: The given pattern,

0.1,

0.110=0.01, 

0.0110=0.001

0.00110=0.0001

Next fraction is 0.000110=0.00001


What is the Error in each of question 123 to 125?

123. A student compared 14 and 0.3. He changed 14 to the decimal 0.25 and wrote, "Since 0.3 is greater than 0.25,0.3 is greater than 0.25 ". What was the student's error?

Ans: we know that 0.3 greater than 0.25

So0.3<0.25

The error is 0.3>0.25


124. A student multiplied two mixed fractions in the following manner: 247×314=617. What error the student has done?

Ans: The mixed fraction is 

247×314=187×134

=9×137×2=11714=8514

But the given value is 617 which is wrong.

Since 247×314=617

Therefore, the error is due to the conversion of mixed fractions into an improper fraction.


125. In the pattern 13+14+15+ which fraction makes the sum greater than 1 (first time)? Explain.

Ans: Given pattern, 13+14+15+

Case I: 13+14+15=20+15+1260=4760 is less than 1.

Case II: 13+14+15+16=20+15+12+1060=5760 also less than 1.

Case III: 13+14+15+16+17=140+105+84+70+60420=459420 is greater than 1.

Hence, 17 makes the sum greater than 1.


-2[1112]  -1[1112] +1[1111]


The NCERT Exemplar solutions for Class 7 Mathematics Chapter 2 contains all the main concepts discussed in the Chapter and helps for better preparation.The NCERT Exemplar for Class 7 Mathematics is the best guide  to make sure you know the Chapter well and have a complete review of all the questions that exist in this activity. The Chapter covers a variety of topics such as Appropriate Fractions, Improper Fractions, Mixed Fractions, Decimal Places etc.


The CBSE NCERT Exemplar for Class 7 Mathematics Chapter 2 contains a total of 5 exercises and 125 questions that are all varied and informative.  These  questions are based on the topics discussed in the Chapter and are represented by theoretical explanations. Exemplary NCERT Exemplar Solutions for Class 7 Mathematics Chapter 2 - Components and Decimals of PDF are available here. Let us now consider some of the topics discussed in this Chapter.

  • Addition, Subtraction, Division and Repetition of Fractions

  • Fraction Multiplication By Total Number

  • Subdivision of Whole Number by Fraction

  • Reciprocal of Fraction

  • Fractional Division by Total Number

  • Multiplication and Division of decimal numbers

 

Key Topics in NCERT Exemplar Solutions for Class Mathematics 7 Chapter 2 - Fractions and Decimals

Proper and Improper Fractions: In NCERT Exemplar Class 7 of Mathematics Exemplar Chapter 2, you will learn about two basic types of fractions, namely - the right fractions and the wrong fractions. If a fraction is in its entirety then it is called the right fraction and if the fraction is a combined combination of the perfect and suitable fractions, then it is called the wrong fraction. When the wrong part is subdivided it is called a mixed fraction. You will learn about the different functions in this Chapter. 


Fractions and Multiplication: The basic concepts and details of duplication of operations are induced in the Chapter. you will learn that to multiply a whole number by the correct subtraction or the wrong fraction, you need to multiply the fraction by a whole number and keep the denominator in its real solution.


Decimals: The basics of Decimals and all the related contexts are discussed in this Chapter. This Chapter will deal with the subtraction of decimal places, the subtraction of integers and mathematical functions and also the  conversion of fractions into decimal values ​​in this Chapter.

WhatsApp Banner

FAQs on NCERT Exemplar for Class 7 Maths Solutions Chapter 2 Fractions & Decimals

1. Describe the topics discussed in NCERT model solutions for Grade 7 Mathematics model Chapter 2 - Fractions and Decimals?

  • The first task starts with multiple-choice questions when given a partial calculation and you need to select the appropriate option from the four possible answers.

  • This consists of the photo options and theory-based statements. These questions are test for the students about their analytical skills that are learnt in the Chapter.

  • Some of the work requires you to fill in the blanks with answers to mathematical questions which have to be applied and considered accurately. The questions require to find the lowest version of a given product.

2. What are the benefits of NCERT Exemplar solutions for Class Mathematics 7 Chapter 2 – Fractions and Decimals?

The team of experts at Vedantu has developed all the solutions in a simple and student-friendly language. It ensures that the students develop a solid understanding of the Chapter and all its contextual concepts. Each question is answered by our team with step-by-step answers and a well-structured explanation. All exemplary answers to section 7 of Chapter 2 statistics are in line with the latest CBSE syllabus. NCERT Exemplar Solutions Mathematics Class 7 Chapter 2 - Free practices and decimals for you.

3. What are Like and Unlike Fractions?

When there is the same denominator then the two fractions are said to be similar. For example, 3/2 and 5/2 are like parts, and we can do addition and subtraction activities. Like:

3/2 + 5/2 = (3 + 5) / 2 = 8/2 = 4

When two fractions have different denominators, they are said to be different from fractions. For example, 3/2 and 4/3 fractions are incorrect and we need to adjust the denominators to make addition and subtraction.

3/2 + 4/3 = (3 × 3) / (2 × 3) + (4 × 2) / (3 × 2)

= (9/6) + (8/6)

= (9 + 8) / 6 = 17/6

4. What is the importance of fractions in daily life?

There are a few ways we unknowingly use fractions while performing our daily routine activities.  The whole world is in fraction we can say. The few examples are f fractions in real life: Eating at a restaurant: Imagine when you go to a restaurant with friends and the waiter brings one building. Divide the amount between friends, using fractions. Pizza: Dividing pizza slices evenly on everyone requires fractions. This is what the like and unlike fractions mean in NCERT Class 7 Chapter 2 Fractions and Decimals.

5. Why is Vedantu a reliable site for downloading NCERT Exemplar Class 7 Mathematics solutions Chapter 2 Fractions & Decimals?

Vedantu has time and again proved itself that it is the most reliable website for downloading study material. These exemplar questions will give the students a wide approach about the Chapter and will encourage them to do their best. As the experts at Vedantu have designed the worksheets keeping in mind the latest question pattern and knowledge of students, the students won’t have any difficulty while learning the same. Moreover, the PDF download is completely free of cost at the Vedantu website. It is highly recommended to try out the Vedantu NCERT Exemplar Class 7 Mathematics Solutions Chapter 2 Fractions & Decimals.