The bicycle with a 30-inches diameter rolls approximately 28.8 more than a tire with the diameter with 21-inches.
How to solve:
- First use the formula: C = 3.14d
- Replace the d value with 30 and solve the equation:
C = 3.14 x 30 ⇒ 94.2477796077
- Then solve the equation again but 21 as the d value:
C = 3.14 x 21 ⇒ 65.9734457254
- Then subtract 65.9734457254 from 94.2477796077 to get the approx. answer of 28.8