Mark builds an apartment that is 16 by 10 feet. There are 6 rooms in total. All the rooms are the same size except the living room which is as big as 3 other rooms. How big is the living room?
Thoughts? Step-by-step reasoning:
Total square footage is 16 * 10 = 160 square feet. . There are 3 + 3 = 6 rooms. 6 - 1 = 5 of them are the same size. If x is the size of the normal room then the square footage of all rooms is 5x + 3x = 8x. So each room is 160 / 8 = 20 square feet. So the living room is 20 * 3 = 60 square feet.
Thus, the answer is 60.