Question

How do you find the circumference of a circle with a diameter of 10 inches?

Answer 1

Hint: In this problem, we have to find the circumference of a circle whose radius is given. We know that for a circle with radius, we can find the circumference. We know that the circumference of a circle is \[2\pi r\] , we can now substitute the value of radius given in this formula and simplify it to get the value of the circumference of the circle. We should also know the value of \[\pi \] to substitute in this problem.

Complete step-by-step solution:
We know that the given diameter of the circle is 10 inches.
We know that the circumference of the circle is,
Circumference of the circle = \[2\pi r\]……. (1)
 We know that, we are given diameter, we can now find the radius as radius is half the diameter
\[r=\dfrac{10}{2}=5\]
We can substitute the above value in the circumference of the circle formula (1),
Circumference of the circle = \[2\times \pi \times 5=10\times \pi =31.42\] inches.
We know that the value of \[\pi =3.14\].
Therefore, the circumference of a circle with the radius 10 inches is 31.42 inches.
 

Note: We should always remember some formulas in geometry, such as area or circumference of the circle. We should remember that the circumference of the circle is \[2\pi r\]. We should also know the value of \[\pi \] = 3.14 to substitute in these types of problems, whenever required. We should also remember that, we have to mention the unit after finding the answer for it.