James has a room that is 13 feet by 18 feet. He increases each dimension by 2 feet. He then builds 3 more rooms of equal size and 1 room of twice that size. How much area does he have?
Thoughts? Step-by-step reasoning:
He increases the length to 13 + 2 = 15 feet. He increases the width to 18 + 2 = 20 feet. So the rooms are 15 * 20 = 300 square feet. So he has 1 + 3 = 4 rooms of this size. So he has 4 * 300 = 1200 square feet of rooms this size. He also has one room of size 300 * 2 = 600 square feet. So he has 1200 + 600 = 1800 square feet of rooms.
Thus, the answer is 1800.