Question

Five bells begin to toll together. They toll at intervals of 2, 3, 4, 6 and 10 seconds
respectively. How many times will they toll together in half an hour excluding the time
when they toll together at the start?​

Answer 1

Answer :- LCM of 2,3,4,6 and 10.

=2*2*3*5=60

They toll together in every one min.

Hence, they toll together 30 times in 30 min.

Now, according to question, we have to exclude one at start.

Therefore,

No. Of times they toll together

is (30-1)=29