From a strictly math point of view the answer is 25 square yards. 1 square yard is 3'x3' From a carpet installers point of view and assuming there is not a pattern to be matched you will need 25-32 square yards if the carpet is 15' wide. If the carpet is 12' wide you will need 28 square yards. If you are shopping for carpet the store will send someone to your house to measure for a more accurate figure.
15 by 15 means 15 multiplied by 15 which would give you a square footage of 225 feet.
182 square feet.
200 square feet.
201.6 square feet.
270 Square Feet.
144 square feet.
126 square feet
31.4167 square feet.
56 SQUARE FEET
200 square feet
A room that is 12 feet by 13 feet is 156 square feet in area
About 288.17 square feet.
96 square feet.