First, to find out how much it is per square foot, divide the cost by the amount he paid for (150/60). This comes to 2.5. So $2.50/square foot. However, we need to know how much he will pay for 240 more square feet. So multiply 2.5 by 240 and you get 600. So, for 240 square ft more roofing, Mr. Lou would pay an additional $600. Hope this Helps!
