Question

A team in science class placed a chalk mark on the side of a wheel and rolled the wheel in a straight line until the chalk mark returned to the same position. The team then measured the distance the wheel had rolled and found it to be 30 cm. To the nearest tenth, what is the area of the wheel? 23.6 cm2 143.3 cm2 286.6 cm2 71.6 cm2

Answer 1

Answer: 71.6
`cm^2` ( approx)

Explanation:

Here, team in science class placed a chalk mark on the side of a wheel and rolled the wheel in a straight line until the chalk mark returned to the same position.

And, The team then measured the distance the wheel had rolled and found it to be 30 cm.

Let r is the radius of the wheel.

Then According to the question,
`2\pi r = 30`

⇒
`r = 30/2\pi`

⇒
`r = 15/\pi`

Thus, The area of the wheel,
`A= \pi r^2= \pi * 15/\pi * 15/\pi`

⇒
`A=1575/22=71.5909090909`≈71.60

Therefore, the area of the wheel = 71.6 square unit.