You have to calculate the probability that it lands on 4. There are 2 possibilities from the 8 that it lands on 4. So the chance is 2/8, which is the same as 4/16
Let x = number of long sleeve shirts
Let y = number of short sleeve shirts
x + y = 200
x/2 + y/3 = 80
Now solve this pair of simultaneous equations to find x and y.
