2025 · Q67
The sum of two numbers is 168. If their HCF is 14, how many such pairs of numbers are possible?
general-mental-abilityquantitative-aptitude
- A1
- B2
- C3
- D0
Explanation
Write the numbers as 14x and 14y with x+y = 168/14 = 12 and x, y coprime. The pairs (x, y) with x+y = 12 are (1,11), (2,10), (3,9), (4,8), (5,7), (6,6); coprimality holds only for (1,11) and (5,7). Hence there are 2 such pairs: (14, 154) and (70, 98).