Question

How many revolutions will a car wheel of diameter 30 in. make as the car travels a distance of one mile?

Answer 1

672 revolutions.

Explanation:

Let n represent number of revolutions.

We are asked to find the number of revolutions it will take for a car wheel of diameter 30 in. to travel a distance of one mile.

We know that 1 mile equals to 63360 inches.

We will use circumference of circle formula to solve our given problem.

`\text{Circumference}=\pi D`, where, D represents diameter of circle.

Now, we will set the product of n and circumference of circle equal to 63360 inches as:

`\pi \cdot 30\cdot n=63360`

`30\pi \cdot n=63360`

`30\cdot (22)/(7)\cdot n=63360`

`n=(63360\cdot 7)/(30\cdot 22)`

`n=(443520)/(660)`

`n=672`

Therefore, it will take 672 revolutions for the wheel of car to travel a distance of one mile.