Question 1160571
Let b = brand new
Let r = refurbished 
3b+2r = 5
b+b+b+r+r = 5
b+b+r
b+r+b
r+b+b

nPr = n!/(n-r)! = 3!/(3-1)! = 3!/2! = 6/2 = 3

There are 3 ways to choose 3 computers that include 1 refurbished computer.