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?	Choose the correct answer:
A) 4 B) 10 C) 15 D) 16 E) 17
L.C.M of 2,4,6,8,10,12 is 120. i.e after each 2 min they will toll together.So in 30 min they will toll 15 times.As they have initially tolled once,The answer will be  15+1= 
<gadget id="calculator"> 15+1</gadget>
<output>16</output>
16.   ANSWER:16
<result>D</result>
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?