Question

-
In
a
School
the
duration
of
a
period
in
junior
Section
is
40 min
and
senior
section is 60min.

If the first bell for each section rings at
at 9am. When will
the two bells ring together again ​

Answer 1

LCM of 60 and 40= 120

therefore they will ring together after 2 hours.

Hope it will help you