Answer:
20
Explanation:
To find the least number of leafs that each collection must have, we find the L.C.M of both numbers. So L.C.M of 4 and 5.
The prime factors of 4 = 2²
The prime factors of 5 = 5
So L.C.M of 4 and 5 = 2² × 5 = 20
So, the least number of leafs that each collection can have is 20 leafs.