Circumference: Applying the formula

Increasing a specific element by addition of.....or multiplication by.......Using Pythagoras' theorem Verifying whether or not the formula is applicable Subtraction or addition to a larger shape A shape consisting of several shapes (requiring the same formula)Using variables Calculating parts of the circle Identifying and defining elements Using additional geometric shapes Worded problems Identify the greater value Finding Area based off Perimeter and Vice Versa Calculate The Missing Side based on the formula

Question 1

O is the center of the circle in the figure below.

What is its circumference?

Question 2

Look at the circle in the figure:

Its radius is equal to 4.

What is its circumference?

Question 3

Look at the circle in the figure.

What is its circumference if its radius is equal to 6?

Question 4

Look at the circle in the figure.

The radius of the circle is $\frac{2}{3}$ .

What is its perimeter?

Question 5

A circle has a radius of 3 cm.

What is its perimeter?

Examples with solutions for Circumference: Applying the formula

Exercise #1

O is the center of the circle in the figure below.

What is its circumference?

Video Solution

Step-by-Step Solution

We use the formula: $P=2\pi r$

We replace the data in the formula: $P=2\times8\pi$

$P=16\pi$

Answer

$16\pi$ cm

Exercise #2

Look at the circle in the figure:

Its radius is equal to 4.

What is its circumference?

Video Solution

Step-by-Step Solution

The formula for the circumference is equal to:

$2\pi r$

Answer

8π

Exercise #3

Look at the circle in the figure.

What is its circumference if its radius is equal to 6?

Video Solution

Step-by-Step Solution

Formula of the circumference:

$P=2\pi r$

We insert the given data into the formula:

$P=2\times6\times\pi$

$P=12\pi$

Answer

$12\pi$

Exercise #4

Look at the circle in the figure.

The radius of the circle is $\frac{2}{3}$ .

What is its perimeter?

Video Solution

Step-by-Step Solution

The radius is a straight line that extends from the center of the circle to its outer edge.

The radius is essential for calculating the circumference of the circle, which can be found using the following formula:

If we substitute in the radius we have, the formula will be:

2*π*2/3

To solve this, first we'll rearrange the formula like so:

π*2*2/3 =

We'll then multiply the fraction by the whole number:

π*(2*2)/3 =

π*4/3 =

4/3π

Answer

$\frac{4}{3}\pi$

Exercise #5

A circle has a radius of 3 cm.

What is its perimeter?

Video Solution

Answer

$6\pi$ cm

Question 1

O is the center of the circle in the diagram.

What is its perimeter?

Question 2

Look at the circle in the figure below.

The radius of the circle equals 5.

What is its perimeter?

Question 3

Look at the circle in the figure below.

The radius of the circle equals 7.

What is its perimeter?

Question 4

Look at the circle in the figure below.

The radius of the circle is equal to 8.

What is its perimeter?

Question 5

Look at the circle in the figure below.

The diameter of the circle is 4.

What is its perimeter?

Exercise #6

O is the center of the circle in the diagram.

What is its perimeter?

Video Solution

Answer

$8\pi$ cm

Exercise #7

Look at the circle in the figure below.

The radius of the circle equals 5.

What is its perimeter?

Video Solution

Answer

$10\pi$

Exercise #8

Look at the circle in the figure below.

The radius of the circle equals 7.

What is its perimeter?

Video Solution

Answer

$14\pi$

Exercise #9

Look at the circle in the figure below.

The radius of the circle is equal to 8.

What is its perimeter?

Video Solution

Answer

$16\pi$

Exercise #10

Look at the circle in the figure below.

The diameter of the circle is 4.

What is its perimeter?

Video Solution

Answer

$4\pi$

Question 1

Look at the circle in the figure.

The diameter of the circle is 10.

What is its perimeter?

Question 2

Look at the circle in the figure.

The diameter of the circle is 12.

What is its perimeter?

Question 3

$\( r=11 \)$

Calculate the circumference.

Question 4

$\( r=7 \)$

Calculate the circumference.

Question 5

$\( r=2 \)$

Calculate the circumference.

Exercise #11

Look at the circle in the figure.

The diameter of the circle is 10.

What is its perimeter?

Video Solution

Answer

$10\pi$

Exercise #12

Look at the circle in the figure.

The diameter of the circle is 12.

What is its perimeter?

Video Solution

Answer

$12\pi$

Exercise #13

$r=11$

Calculate the circumference.

Video Solution

Answer

69.115

Exercise #14

$r=7$

Calculate the circumference.

Video Solution

Answer

43.982

Exercise #15

$r=2$

Calculate the circumference.

Video Solution

Answer

12.56

Question 1

$\( r=6 \)$

Calculate the circumference.

Question 2

A circle has a diameter of 12.

What is its perimeter?

Question 3

Look at the circle in the figure.

If its diameter is 5, then what is its circumference?

Question 4

Look at the circle in the figure.

Given that its radius is equal to 3, what is its circumference?

Question 5

Given the circle whose radius has a length of 9 cm

What is its perimeter?

Exercise #16

$r=6$

Calculate the circumference.

Video Solution

Answer

37.699

Exercise #17

A circle has a diameter of 12.

What is its perimeter?

Video Solution

Answer

12π

Exercise #18

Look at the circle in the figure.

If its diameter is 5, then what is its circumference?

Video Solution

Answer

$5\pi$

Exercise #19

Look at the circle in the figure.

Given that its radius is equal to 3, what is its circumference?

Video Solution

Answer

$6\pi$

Exercise #20

Given the circle whose radius has a length of 9 cm

What is its perimeter?

Video Solution

Answer

56.55