Multiple choice

four bells ring together at 12 noon.frequency of bell ringing is 3, 4, 5, 7 seconds respectively.next time they will ring together?

  1. 12:05 pm

  2. 12:07 pm

  3. 12:09 pm

  4. 12:12 pm

  5. 12:15 pm

Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

when the bells will ring together is determined by Lcm of the numbers. the Lcm of 3,4,5,7 is 420, which means 7 minutes.