How many square feet are in a 12 x 16 room?

Answer 1

The short answer is 12 x 16 = 192 ft2

Think of it this way: if you have a stack of 1 ft x 1 ft tiles, you can lay a row of 12 along the short wall. Then you can keep laying rows until you have 16 along the long wall - 16 rows of 12 or 12 rows of 16 - count the tiles and you always get 192.