Question

A mountain bike tire completes 40 revolutions and travels 272 feet. Rounded to the nearest inch, what is the diameter of the bike's tire? Use 3.14 for pi.​

Answer 1

• 26 inches

Step-by-step explanation:

When the tire does not slip, each revolution means that the bike advance a distance equal to the circumference of the tire.

Thus, when 40 revolutions are completed, the bike will advance a distance equal to 40 times the circumference of the bike:

• distance = 40 × circumference

The circumference is equal to:

• circumference = 2π × radius

Using π = 3.14:

• 272 feet = 40 × 2 × 3.14 × radius

• radius = 1.0828 feet

• diameter = 2 × radius = 2.1656 feet

Convert to inches: 1 feet = 12 inches:

• diameter = 2.1656 feet × 12 inches/feet = 25.9872 inches ≈ 26inches