Answer: 1278 dollars
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Work Shown:
3 feet = 1 yard
12 feet = 4 yards (multiply both sides by 4)
30 feet = 10 yards (multiply both sides of the original equation by 10)
The carpet is 12 feet by 30 feet. This is the same as saying the carpet is 4 yards by 10 yards
Multiply the new length and width to get...
A = L*W
A = 10*4
A = 40
The area is 40 square yards. Multiply this by the cost per square yard (31.95) to get the total cost in dollars
40*31.95 = 1278