Question

If sum of two numbers is 1215 and their HCF is 81, then the possible number of pairs of such numbers are ______.

Options

• 2

• 3

• 4

• 5

Answer 1

If sum of two numbers is 1215 and their HCF is 81, then the possible number of pairs of such numbers are 4.

Explanation:-

Since HCF = 81, two numbers can be taken as 81x and 81y,

ATQ 81x + 81y = 1215

Or x+y = 15

which gives four co prime pairs -

1,14

2,13

4,11

7, 8