What will it cost to carpet a room 12 feet wide and 15 feet long if carpeting costs 20.80 per square yard?

Convert the feet to yards first.

12 feet = 4 yards

15 feet = 5 yards

4 yards x 5 yards = 20 square yards.

The price is (20 square yards) x ($20.80 per square yard) = $416.00

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If you don't convert the feet to yards first, make sure to be very careful with the number of square feet.

12 feet x 15 feet = 180 square feet.

Trying to convert to square yards by dividing by 3 will give you 60 foot-yards, which isn't right, so you have to divide by 3 again to get 20 square yards (i.e there are 9 square feet in a square yard).