Question

Three bells are ringing continuously at intervals of 30, 36 and 45 minutes respectively
At what time will they ring together again if they ring simultaneously at 8 a.m.?
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Answer 1

We are given that three bells are ringing continuously at intervals of 30, 36 and 45 minutes respectively.

First find the least common multiple of 30, 36 and 45.

3 |30, 36, 45

5 |10, 12, 15

3 |2, 12, 3

2 |2, 4, 1

2 |1, 2, 1

1 |1, 1, 1

So, LCM of 30, 36 and 45 is 3 × 5 × 3 × 2 × 2 = 180

So, after 180 minutes they ring together.

60 minutes = 1 hour

So, 180 minutes = 3 hours

So, after three hours they ring together

Therefore, they all ring together again if they ring simultaneously at 8 a.m. at 11 a.m.

Hope it Helps uh....