The giant earthmover used for open-air coal mining has rubber circular tires 11.5 feet in diameter. How many revolutions does each tire make during a six-mile trip? Express your answer to the nearest whole number.
In each revoution, the tire travels pi * diameter = 11.5 pi ft (1)
6 mlies = 6 * 5280 ft (2)
So....the number of revolutions that the tire makes is (2) / (1) =
[ 6 * 5280 ] /[ 11.5 * pi ] ≈ 877 revolutions
+77 
