How many 4x8 sheets of plywood does it take to cover a 960 square foot roof?

The area of a 4x8 sheet of plywood = 4*8 = 32 square feet.

Divide total area by area of 1 piece of plywood:

960 / 32 = 30 sheets of plywood total.

First convert 75% to a number by moving the decimal place to the left two places. That gives us .75. Now to figure out what 75% of $8 is we multiply .75 by 8. You should end up with $6. Now you subtract the discounted price from the original and it gives you $8-$6=$2.