Answer: 6.25 inches (choice C)
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Explanation:
The jump from 4 inches to 5 inches is 5/4 = 1.25
In other words, 4*1.25 = 5
So we need to multiply every dimension by the scale factor 1.25 to enlarge the image. The 5 inch dimension then goes to 5*1.25 = 6.25 inches
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Here's another way you can solve
(old width)/(old length) = (new width)/(new length)
4/5 = 5/x
4x = 5*5
4x = 25
x = 25/4
x = 6.25
