Your answer is the lst bubble. divide 18 by 2 and you get 9. with that you multiple 9 x 9 which = 81. since pi is 3.14 you multiple 81 and 3.14 and you grt 254.34! hope this helped :)
<em>If the radius is 18 inches, the diameter is 3 feet. The circumference of the tire is therefore 3π by C=d(π). After 200 revolutions, the tire and car have gone 3π x 200 = 600π feet.</em>
