The ratio of two numbers is 3:4 and their HCF is 5. Find the numbers.

A10, 15

B15, 20

C20, 25

D5, 10

Explanation

When the HCF is 5, the numbers must be 3 × 5 and 4 × 5, which gives 15 and 20.
Both conditions check out: 15 : 20 reduces to 3 : 4, and the HCF of 15 and 20 is 5.
Option A 10, 15 has the ratio 2 : 3, so it fails the ratio condition.
Option C 20, 25 has an HCF of 5 but a ratio of 4 : 5, so it fails the other condition.
General pattern: two numbers in the ratio a : b with HCF h are always ah and bh.
Ratio and HCF questions in PPSC and NTS papers usually come down to this single substitution.

Submitted by: mcqstutor Team More Mathematics MCQs →