Huey's Hip Pizza sells two sizes of square pizzas: a small pizza that measures 12 inches on a side and costs $10, and a large pizza that measures 18 inches on a side and costs $20. If two friends go to Huey's with $30 apiece, how many more square inches of pizza can they buy if they pool their money than if they each purchase pizza alone? Choose the correct choice from the following answers:
A) 5 square inches
B) 36 square inches
C) 15 square inches
D) 25 square inches
E) 350 square inches

Rationale: "in the first case each can buy one pizza of $ 10 and one pizza of $ 20 . in square inches that would be ( 12 * 12 = 144 ) for the small pizza and ( 18 * 18 = 324 ) for the large pizza . in total sq inches that would be ( 144 + 324 ) * 2 = 936 sq inches . in the second case if they pool their money together they can buy 3 large pizzas . in terms of square inches that would be 3 * 324 = 972 sq inches . hence , the difference is 36 square inches more ( 972 - 936 ) . the correct answer is b"
Answer: B