Question

three bells ring at regular intervals of 10 and 12 days in together at 6 a.m. when will live in together again

Answer 1

Hi,

This problem based on the concept

of LCM.

Here we have to find LCM of intervals

9 , 12 , 15 minutes which indicates

after how long they all again toll

together.

Write 9 , 12 and 15 product of prime

factors,

9 = 3 × 3

12 = 2 × 2 × 3

15 = 3 × 5

LCM( 9 , 12 , 15 ) = 3 × 3 × 2 × 2 × 5

= 180

Three bell toll together after 180

minutes .

I hope this will useful to you.

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