Six bells commence tolling together and toll at intervals of 4, 6, 8, 10, 12 and 14 seconds respectively. In 70 minutes, how many times do they toll together ?
Choose the correct choice from the following choices:
A) 2  B) 3  C) 4  D) 5  E) 6
LCM of 4, 6, 8 10, 12 and 14 is 840.   So, after each 840 seconds, they would toll together.   Hence, in 70 minutes, they would toll 70*60 seconds / 840 seconds = 5 times   But then the question says they commence tolling together. So, they basically also toll at thebeginning(0second).   So, total tolls together = 5+1= 
<gadget id="calculator">5+1</gadget>
<output>6</output>
6   Answer: 6
<result>E</result>
Six bells commence tolling together and toll at intervals of 4, 6, 8, 10, 12 and 14 seconds respectively. In 70 minutes, how many times do they toll together ?