Question

Four bells begin to ring together and ring respectively at intervals of 6,7,8 and 12 sec. How many times they will ring together in 1 hour ,excluding the one at start.

Answer 1

Answer:

18 times

Step-by-step explanation

L.C.M of 6,7,8,12 is 168 sec

now divide 168 by 3600sec because we want to know in an hour

so after dividing 168 by 3600 we get 19 times

now by excluding the first one we get 18 as our answer

Answer 2

Answer:

6 in 1sec

Step-by-step explanation:

6+7+8+12+6+7+8=54sec =6tyms