Question

six bells commerce toll at intervals of 2,4,6,8,10,12, minutes respectively. In 30 hours , how many times do they toll together?​

Answer 1

According to question, they toll at intervals of 2, 4, 6, 8, 10, 12 minutes.

Then, they told together after LCM(2,4,6,8,10,12) minutes

LCM(2,4,6,8,10,12) = 120

So, they toll together after every 120 minutes.

In order to find how many times they toll together in 30 hours, first convert 30 hours into minutes then divide it by 120.

1 hr = 60 min

30 hours = 30*60 = 1800 mins

No. of times they toll together in 1800 mins = 1800/120 + 1 = 15 + 1 = 16 times