Answer:
The difference in square feet is 75 square feet.
Explanation:
Formula for area of a rectangle: Area = length x width
Current measurements: 12 by 10, so
A = 12 x 10 = 120 square feet
New measurements: 15 by 13 (adding 3 feet to each)
A = 15 x 13 = 195 square feet
Subtract to find the difference:
195-120 = 75
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