Question

in a shop, there are three clocks which chime at interval of 15, 20 and 30 minutes respectively. they all chime together at 2 pm. at what time will they all chime together again?

Answer 1

The clocks chime at intervals of 15, 20, 30 minutes respectively..
All chime together at 2 pm.
All will together chime again in LCM of 15, 20 and 30  minutes.

So  the LCM is 60 min or 1 hour.

So they will chime again at  3 pm,  then at 4 pm,  at 5 pm and so on.

Answer 2

Here ,we have to find the LCM of 15,20 and 30, which is 60 minutes/1 hour.

So, the clocks will chime again at 3 pm, 4 pm ,5 pm, 6 pm and so on.