The tires on your bicycle have a radius of 8 inches. How many rotations does each tire make when you travel 700 feet? Round your answer to the nearest whole number. Please help me

Accepted Solution

"One rotation" would be the circumference of the wheel, which is

C = 2*pi*r, or  (here)  C = 2*pi*(8 inches) = 16*pi inches.

                                                                       1 ft
Convert this to feet:  16*pi inches  times  ---------------
                                                                   12 inches

Here "inches" cancels out and you are left with (4/3)pi ft.

So, one rotation of the wheel moves you and your bike forward (4/3)pi ft.

Divide this into 700 feet:

700 ft            2100 
------------- = --------- rotations = 525 rotations (answer)
(4/3) pi ft        4