Three bells rings at the intervals of 36 seconds, 40 seconds and 48 seconds respectively. They start ringing together at a particular time. When they will start ringing together again?
(1)After 6 minutes
(2) After 12 minutes
(3)After 18 minutes
(4) After 24 minutes

• Option 2 12 minutes
  
  LCM of 36,40,48 is 720
  720/60=12
  
• 12 years agoHelpfull: Yes(26) No(5)
• after 12 minutes .
  6*60=360
  12*60=720
  18*60=1080
  24*60=1440.so answer is 36*20=720 and 40*18=720 and 48*15=720
• 12 years agoHelpfull: Yes(2) No(9)
• THE Highest Common Factor (HCF) of 36,40 and 48 is 720.....
  
  i.e., 720 seconds...
  
  when converted to Minutes it is 12min
• 11 years agoHelpfull: Yes(1) No(1)
• 12 minute
  
• 12 years agoHelpfull: Yes(0) No(2)
• LCM of 36,40,48
  LCM = 2^4 * 5 * 3^2
  = 720
  convert it into min = 720 / 60
  = 12 min
  option (b)
• 8 years agoHelpfull: Yes(0) No(0)
• 36=3^2x2^2
  40=5x2^2
  48=3x2^4
  so LCM=2^4x3^2x5
  it is in seconds convert in minutes divide this by 60
  so we get 12 minutes
• 7 years agoHelpfull: Yes(0) No(0)