If Gretta's bicycle has a 25-inch radius wheel, how far will she travel in two turns of the wheel? (π = 3.14)

a. 491 in

b. 78.5 in

c. 100 in

d. 157 in

d. To determine how far the wheel will travel, determine the circumference of the wheel multiplied by 2. The formula for the circumference of the wheel is πd. Since the diameter of the wheel is 25 inches, the circumference of the wheel is 25π. Multiply this by 2, (2)(25π) or 50π. Finally, substitute 3.14 for π; 50(3.14) = 157 inches, the distance the wheel traveled in two turns. If you select a, you used the formula for area of a circle rather than circumference. If you select b, the distance traveled was one rotation, not two.