Question

Jim has 20-inch wheels on his bicycle (their diameter is 20 inches). The tires are worn out, and he would like to cut them into pieces to use as a bumper on something he's making. Estimate the length of rubber Jim would get from his two bicycle tires.

≈ 120 in.
≈ 40 in.
≈ 60 in.
≈ 136 in.

Answer 1

Each tire length ≈ circumference = π·diameter = π·20 ≈ 62.8 in.
Two tires ≈ 2·62.8 ≈ 125.6 in, so the closest choice is ≈ 120 in.