Question

a bell rings every 8 miniutes and another 10 minutes. they both ring together at midnight. what time will they both ring at the same time again

Answer 1

$\hbox{lcm} (8,10)=40$

They will ring at the same time again 40 minutes later that is at 0:40.

Answer 2

12.40 am is the next time they both ring at the same time