Answer:
first we need to find the LCM of the given numbers i.e. 8, 12, 15 and 20
2*2*2*5*3=120
Then
as 2, 3, 5 are not in pairs, we need to multiply the LCM with 2*5*3=30
so,
least perfect square number which is divisible by each of numbers 8 12 15 and 20
=120*30=3600
