There are 640 acres in a square mile, and 5280 feet in one mile. What is the length in feet (to the nearest foot) of the side of a square having an area of one acre?
A) 660 feet
B) 209 feet
C) 165 feet
D) 412 feet
E) 435 feet

Question

Quizplus · Accepted Answer

There are 640 acres in a square mile, so one acre is 1/640 of a square mile. Since a mile is 5280 feet, a square mile is 5280^2 square feet. Therefore, one acre is (5280^2)/640 square feet. The side of a square with this area is the square root of ((5280^2)/640), which is approximately 208.71 feet, rounded to 209 feet.

There Are 640 Acres in a Square Mile, and 5280