Bunuel wrote:

A pilot surveys a flat circular area represented by 4π square inches on a map. If 1 inch on the map represents 60 miles, how many square miles does the pilot survey?

(A) 15π

(B) 240π

(C) 900π

(D) 7,200π

(E) 14,400π

Since 1 inch = 60 miles, 1 square inch = 60 x 60 = 3,600 square miles.

Thus, 4π square inches = 4π x 3,600 = 14,400π square miles.

Alternate Solution:

We can create a proportion to solve this question. First, the scale given for the map must be converted to square miles: since 1 inch is 60 miles, 1 square inch = 60 x 60 = 3600 square miles.

The proportion for the number of square miles the pilot surveys is:

1 square inch/3600 square miles = 4π square inches/x

Cross multiplying, we have:

x = 4π x 3600

x = 14,400 π square miles

Answer: E

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