RD Sharma Class 8 Solutions Chapter 10 - Direct and Inverse Variations (Ex 10.1) Exercise 10.1 - Free PDF

RD Sharma Class 8 Chapter 10  Direct and Inverse Variation is provided here. We have included solutions to questions based on the topic of Direct and Inverse Variation to solve real-life problems. 

In this exercise, students will understand the meaning of variations and the concept of variations. This chapter mainly deals with two types of variations namely, Direct Variation and Indirect Variation. There are several examples of day to day life where the knowledge of proportions is utilized.

For illustration:

• If three girls arrange flowers in 18 minutes, how long will 7 girls take?

• If while making coffee for 1 person we use 1 spoon of stevia, then how many spoons will we need for making coffee for 4 people?

We can clearly understand that there is a relation between the change of one quantity and another quantity, from the above illustrations. The idea of variation conveys that quantities of two things are related to each other in such a manner that an increase or decrease in one leads to an increase or decrease in the other.

Some of The Topics Which are Discussed in This Chapter are as Follows: 

• Direct Proportion.

• Indirect Proportion.

Direct Proportion

Let us learn the definition of direct proportion. 

Two quantities a and b are in direct proportion when they fulfill the following listed conditions:

• If a increases then b increases too.

• If a decreases then b decreases too.

• a/b = C where C is a constant or, a = C * b. 

The ratio of the respective values of x and y remain the same, despite an increase or decrease in their values.

We can denote b is proportional to a by the symbol ∝ , i.e. b ∝ a. 

Some real-life examples where the concept of direct proportion is utilized are: 

• If the amount of sugar bought increases, its price increases too.

• More is interest earned when more money is deposited in a bank.

Inverse Proportion

Let us now understand the concept of Inverse Proportion. 

Two quantities a and b, are said to be in inverse proportion if they fulfill the following criteria:

• If a increases then there is a decrease in b.

• If a decreases then there is an increase in b.

• a * b =  K. Here K is a constant.

This means that despite an increase or decrease in their values the ratio of the respective values of a and b remain the same.

We symbolize a is inversely proportional to b by the notation y ∝ 1/x. 

Some Real-Life Examples Where The Concept of Inverse Proportion is Utilized are:

• If the number of workers increases, the time to complete the work will decrease.

• The time taken to cover a distance decreases as the speed of a vehicle increases.

For students who wish to perform well in Math, RD Sharma Solutions is the best study material. The subject experts at Vedantu have prepared the  RD Sharma solutions to help the students who are finding difficulties in solving them. Students can easily access answers to the problems present in RD Sharma Class 8 Chapter 10  by downloading the PDF. It contains all solutions in a detailed manner and also one can expect these questions to be asked in the exam. After solving these questions students will be more confident about their performance.