A border of uniform width is placed

A border of uniform width is placed around a rectangular photograph that measures 8 inches by 10 inches. If the area of the border is 144 square inches, what is the width of the border, in inches?

2 Explanations

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Alan Man

The other way to solve this is to think about the area of the smaller vs. larger rectangle.

Smaller rectangle area = 8 x 10

Large rectangle area must be increased in the same proportion. So if we increase it by the first example width (i.e. 3), then it must be (8+3+3) and (10+3+3) i.e. 16x14=224

224 less 80 = 144 which is the area, therefore width is 3.

Mar 16, 2017 • Comment

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Mike McGarry, Magoosh Tutor