2. Six bells commence tolling together and toll at intervals of 2, 4, 6, 8, 10 and 12 seconds respectively. In 30 minutes, how many times do they toll together?
(A) 4 (B) 10 (C) 15 (D) 16
 
This is a olympaid question so solve wisely but explain with steps

Asked by sucharitasahoo1 | 30th Nov, 2017, 08:58: PM

Expert Answer:

begin mathsize 16px style LCM space of space 2 comma space 4 comma space 6 comma space 8 comma space 10 space and space 12 space equals space 120 space seconds space equals 2 space minutes
Hence comma space all space the space 6 space bells space will space ring space together space in space every space 2 space minutes.
rightwards double arrow Number space of space times space they space will space ring space together space in space 60 space minutes equals 60 over 2 plus 1 equals 30 plus 1 equals 31 end style

Answered by Rashmi Khot | 1st Dec, 2017, 09:34: AM