Question

In a school the duration of a class inthe primary section is 40 and secondary section it is 1 hour. If both sections begin at 9a.m when will bells of the two sections ring together again?

Answer 1

p1 =40
p2=60
after 6 period inp1 240 min
after 4 period in p2 240 min
so 240/60=4 hour
so 9+3=12 am
so 12am+1hr=1pm