Question

Three bells ring respectively at an interval of 15 seconds, 20 seconds and 24 seconds. if they ring continuously for 12 minutes then how many times, during this period, will they ring together?

Answer 1

i think the answer i 600 seconds

Answer 2

Answer:6 times

LCM of 15,20,24

15= 3*5

20= 2*2*5

24= 2*2*2*3

LCM= 2*2*2*3*5=120sec

1 times=120sec

720sec=720/120=6times

(1min=60sec

12min=12*60=720sec)