Question

three Bells in a temple toll at every 10 minutes 18 minutes and 30 minutes respectively if they toll together at 7 a.m. then that time among the following at which they will toll together again is options are A.)1 .30 pm. B.) 2.30 pm. C.) 3.30 pm and D .) 3.00pm

Answer 1

Answer:  The correct option is (B) 2 : 30 pm.

Step-by-step explanation: Given that three bells in a temple toll at every 10 minutes 18 minutes and 30 minutes respectively.

If they toll together at 7 a.m. then we are to select the time among the options at which they will toll together again.

The L.C.M. of 10, 18 and 30 is

L.C.M.(10, 18, 30) = 90.

So, the bells rang at an interval of 90 minutes, that is 1 : 30 hours.

Since they rang at 7 a.m. in the morning, so the next time they rang together will be

7 : 00 + 1 : 30 = 8 : 30 am,

8 : 30 + 1 : 30 = 10 : 00 am,

10 : 00 + 1 : 30 = 11 : 30 am,

11 : 30 + 1 : 30 = 1 : 00 pm,

1 : 00 pm + 1 : 30 =2 : 30 pm.

Therefore, the correct option is (B) 2 : 30 pm.