Answer:
1/114 or 0.008772
Step-by-step explanation:
I am not very sure, my answer seems unlikely, but here's what I think:
There are 20 jerseys in the box to begin with, and 5 medium jerseys that you can have.
Therefore, the probability of you randomly grabbing a medium sized jersey is 5/20 or 1/4.
After taking out one medium sized jersey, there are 19 jerseys in the box and 4 medium jerseys you can pick from.
The probability of you randomly grabbing a medium sized jersey is 4/19.
After taking out another medium sized jersey, there are 18 jerseys left in the box and 3 medium jerseys you can pick from.
The probability of you randomly grabbing a medium sized jersey is 3/18.
To get the answer, you do 1/4 * 4/19 * 3/18, and get 1/114, or 0.00877192982.
If you round that to the nearest millionth, it's 0.008772
Don't judge me, it might not be correct.