Math Expression: Circumference of a Circle Practice Question

Given a circle with the radius of 9.42ft. Find the circumference of this circle. Take π as 3.14.

Step 1

The picture below shows the circle with the diameter d.
Step 2

To find the diameter of the circle, we start with the formula for the circumference of a circle:
Step 3

Since the value of the circumference is given as 9.24ft, we can substitute C with 9.24. Similarly, we can substitute π with 3.14. This is shown below:
Step 4

Now, we have 3.14d = 9.24. To find d, we need to remove 3.14. To do so, we divide both sides of the equation with 3.14 as shown below:
Step 5

Now, the calculated number has no meaning unless we include the unit for it. Since the circumference is in feet, the diameter will also be in feet. Hence:

d = 3ft
Step 6

Therefore, the answer is A.