Question

Three bells ring at intervals of 15, 20 and 30 minutes. If they all ring together at 11 a.m together, at what time will they ring together again.

Answer 1

LCM of 15, 20, 30 minutes = 60 minutes = 1 hr

So they will ring together after every 1 hr

As they ring together at 11 am so they will again ring after one hour

i.e,. 11 +1 = 12 PM

Answer 2

Answer:

Step-by-step explanation:

LCM of 15, 20, 30 minutes = 60 minutes = 1 hr

So they will ring together after every 1 hr

As they ring together at 11 am so they will again ring after one hour

i.e,. 11 +1 = 12 PM