Question

Four bells commence tolling together and toll at intervals of 2.3.6 and
8 seconds respectively. In 90 minutes, how many times do they toll together?​

Answer 1

Answer: 3 times. At 24, 48, 72 seconds.

Step-by-step explanation: we find numbers which are multiple of all given intervals, 2, 3, 6, 8.

Alternatively, we find LCM of above digits and LCM should be less than or equal to 90.