1:- Three Bells toll at intervals of 12 minutes, 15 minutes and 18 minutes respectively. If they start tolling together, after what time will they next toll together?
a) 12 minutes
b) 15 minutes
c) 120 minutes
d) 180 minutes
Answer -
The bells toll at intervals of 12 min, 15 min and 18 min, respectively. (given)
After they start together, they would meet at the time when their tolling interval coincides i.e. The L.C.M of 12 15 and 18.
12 = 2*2*3
18 = 3*3*2
15 = 3*5
L.C.M is the product of distinct factors raised to the highest powers,
Thus, the L.C.M is:
2*2*3*3*5 = 120 minutes.
Hence, they will toll together after 120 minutes of starting
Tags:
Real Number