Answer :
for this, we need to find the lowest common multiple of 10 and 8
multiples of 10 : 10,20,30,40,50
multiples of 8 : 8,16,24,32,40
so the LCM of 10 and 8 is 40
therefore, they will both flash at the same time again in 40 seconds.
multiples of 10 : 10,20,30,40,50
multiples of 8 : 8,16,24,32,40
so the LCM of 10 and 8 is 40
therefore, they will both flash at the same time again in 40 seconds.