Question

If 35 inland letters cost Rs. 87.50. Show how many such letters can we buy for Rs. 315?

Answer 1

Hint: We will first find the number of letters bought for Rs. 1 by dividing the number of letters by the total cost of letters. Then, multiply 315 with the number of letters for Rs. 1 to find the number of letters for Rs. 315.

Complete step-by-step answer:
We are given that the cost of 35 inland letters is Rs. 87.50.
We have to find the number of letters the person can buy for Rs. 315.
We will first find the number of letters that can be bought for Rs. 1
For that, we will divide 35 by 87.50.
$\dfrac{{35}}{{87.50}} = 0.4$
Now, we will determine the number of letters that can be bought for Rs. 315
Therefore, we multiply the number of letters bought for Rs. 1 by 315.
That is,
$0.4 \times 315 = 126$
Hence, a person can buy 126 letters for Rs. 315.

Note: For these types of questions, we generally use unitary methods. That is, we first find the number of things that can be bought for a unit amount and then multiply the required amount. One has to be careful that we have to divide the number of letters by the total cost of letters to find the number of letters bought in Rs. 1, and not the vice-versa.