Solution:
Concept: By dividing the entire number of letters by their cost, we can first calculate how many letters were purchased for one rupee. The number of letters for Rs. 315 is then determined by multiplying 315 by the number of letters for Rs.315We are informed that Rs. 87.50 will be required to send 35 inland letters.
The quantity of letters that can be purchased for Rs. 315 must be determined.
We shall first determine how many letters may be purchased for one rupee.
To do it, multiply , which equals
We will now calculate how many letters can be purchased for
We then multiply the quantity of letters purchased for
So, for Rs. 315, one can purchase 126 letters.
Hence, the answer is 126.