1986 AMC 12 Problem 8

Question

The population of the United States in

1980

was

226{,}504{,}825.

The area of the country is

3{,}615{,}122

square miles. There are

(5280)^2

square feet in one square mile. Which number below best approximates the average number of square feet per person?

5{,}000

10{,}000

50{,}000

100{,}000

500{,}000

Divide total square feet by population

Round the given values to two significant digits before multiplying

The average is approximately

\begin{aligned} &\frac{(3.615\times10^6)(5280)^2} {2.265\times10^8}\\ &\qquad\approx 4.45\times10^5 \end{aligned}

square feet per person. Of the choices, this is closest to

500{,}000.

Thus the correct answer is E.

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