Question

I don’t understand it doesn’t make sense

Answer 1

Answer: 3 inches

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Work Shown

• A = width on paper = 9 inches
• B = width on screen (actual width) = 60 ft
• C = height on paper = unknown amount of inches
• D = height on screen (actual height) = 20 ft

A/B = C/D

(9 inches)/(60 ft) = (C inches)/(20 ft)

9/60 = C/20

9*20 = 60C

180 = 60C

60C = 180

C = 180/60

C = 3

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Another approach

The jump from "20 ft" to "60 ft" is "times 3", which reverses to "divide by 3".

So if we know the width is 9 inches on paper, then its height must be 9/3 = 3 inches.