Answer: 5
Explanation:
Given : Jerome is making prizes for a game at the school Fair.
He has two bags of different pins, one with 15 Square pins and one with 20 round pins.
Every prize will have One of a Kind Pin.
Each prize will have the same number of pins.
Then to find the greatest number of pins Jerome can put in each prize we need to find the greatest common factor of 15 and 20.
Prime factorization of 15 and 20 :-

We can see that the greatest common factor of 15 and 20 =

Hence, the greatest number of pins Jerome can put in each prize = 5