Question

3 bells ring at an interval of 4,7 and 14 minutes. All three bells rang at 6 am. How many times

will the three bells ring together between 6 am and 12 noon?​

Answer 1

Answer:

The intervals of ringing of these 3 bells are 4,7 and 14 minutes. so, Minimum time after which these all 3 bells will ring = LCM(4,7,14) = 28 min. so, After 28 minutes , these all 3 bells will ring together. And, so, these bells will ring together at 6:28 am

please mark as Branilst answer

Answer 2

Answer :-

It is given that, 3 bells ring at an interval of 4 , 7 and 14 minutes. So, they will rang together after :-

LCM of 4 , 7 , 14 :-

$\begin{array}{c|c} \underline{\sf {2}}&\underline{\sf {\; \; 4,7,14 \; \; \: }} \\ \underline{\sf {2}}&\underline{\sf {\; \; 2,7,7\; \; \: }}\\ \underline{\sf {7}}&\underline{\sf {\; \; 1,7,7 \; \; \: }} \\ & {\; \; 1,1,1 \; \; }\end{array}$

LCM = 2 × 2 × 7 = 28

Hence, the bells will rang together after 28 minutes.

Now, it is given that bell rang at 6 am. So, they will rang together at 6:28 , 6:56 and so on.

We are asked how many times will it rang between 6 am and 12 noon. As there are 6 hours, minutes = 6 × 60 = 360 minutes.

So, number of times bells rang = 360 / 28

= 12 ( only integer part )

Hence, number of times bells rang together between 6 am to 12 noon is 13 ( including the bells rang at 6 am )