Question

Two bell P and Q ring at intervals of 3 hours and 4 hours, respectively. After how many hours will the two bells first ring simultaneously ​

Answer 1

This problem is same as finding the least common multiple (LCM) of 3 and 4.

3 = 3

4 = 2 x 2

=> LCM = 3 x 2^2 = 12 (3 appears once, 2 appears twice)

=> After 12 hours, two bell P and Q ring simultaneously.

Hope this helps!

:)