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 ?

• If you find LCM of the give intervals, you will get the point of time when all of them toll together. LCM of 2,4,6,8,10,12 is 120sec = 2min. Every 2 min they toll together.So in 30 min they toll together 15 times.
• 13 years agoHelpfull: Yes(18) No(5)
• 16
• 13 years agoHelpfull: Yes(7) No(5)
• Lcm of 2,4,6,8,10,12 is 120
  30min.=1800sec.
  no.of times they collide-1800/120=15
• 13 years agoHelpfull: Yes(4) No(3)
• Answer: 15 times
  six bells start tolling together so they next time toll together after 120 seconds(i.e. LCM of 2,4,6,8,10,12)
  thus in 30 X 60=1800 seconds they will toll together (1800/120)=15 times
• 13 years agoHelpfull: Yes(4) No(3)
• the lcm of 2,4,6,8,10,12 is 120
  therefore in every 120th sec or in every 2nd minute all bells toll together.
  so in 3o mins all bells toll 15 times together
  Ans:15
• 13 years agoHelpfull: Yes(3) No(4)
• 15
• 13 years agoHelpfull: Yes(3) No(2)
• hello dear suchandra raavi , ans shud b 16. chek it out....
• 12 years agoHelpfull: Yes(3) No(1)
• bells toll together after evry 2sec.
  30 min=30*60 sec=1800 sec
  thus they toll 1800/2=900 times! :)
• 13 years agoHelpfull: Yes(2) No(15)
• Dear sir, how can we consider the 0th second. i think answer is 15 seconds......
  
• 10 years agoHelpfull: Yes(0) No(0)