Given the dimensions of 72 yards by 1.5 yards, we can find that the total area of material the manufacturer has is 72 x 1.5 = 108 sq. yards. Dividing this by the 2.7 sq. yards required per shirt, they can make 108/2.7 = 40 shirts.
First you want to add all the numbers up. Then you have to subtract from the amount of white balls (which will give you seven). Put 7 above the sum of all the balls and so the chances of getting a ball that is not white would be 7/13.