Question

The price of 10 chairs is equal to that of 4 tables. The price of 15 chairs and 2 tables together is Rs. 4000. Find the total price of 12 chairs and 3 tables.
A) Rs 3500
B) Rs 3750
C) Rs 3840
D) Rs 3900

Answer 1

Hint: We can assume the cost of one chair to be one variable and the cost of one table to be the other variable and solve the problem simultaneously and then find out the values of the variable and solve for the question.

Complete step-by-step answer:
Let the price of one chair be Rs $x$and the price of one table be Rs $y$.
Therefore, the cost of ten chairs = $10 \times x = Rs10x$
 Therefore, the cost of four chairs = $
  4 \times y = Rs4y \\
    \\
$
According to the statement given in the question we get
$
  10x = 4y \\
  x = 0.4y \\
$
Cost of 15 chairs = $
  Rs15x \\
    \\
 $
Cost of 2 tables= $Rs2y$
According to the condition given in the question we get
$
\Rightarrow 15x + 2y = 4000 \\
\Rightarrow (15 \times 0.4y) + 2y = 4000 \\
\Rightarrow 6y + 2y = 4000 \\
\Rightarrow 8y = 4000 \\
\Rightarrow y = Rs500 \\
\Rightarrow x = 0.4y = 0.4 \times 500 \\
\Rightarrow x = Rs200 \\
$
Price of 12 chairs = $12 \times 200 = Rs2400$
Price of 3 tables = $3 \times 500 = Rs1500$
Therefore, the total price of 12 chairs and 3 tables = $2400 + 1500 = Rs3900$
Therefore, the correct option is Option D


Note: : This is a relatively simple question. Only a little bit of calculation has to be done. Prior knowledge of algebra and how to solve simultaneous equations is necessary otherwise it will take a long time before we arrive at the right answer. Other than that part there is nothing special in the problem, or there isn’t any catch in the problem. But we should always do the calculations accurately .