All GED Math Resources
Example Questions
Example Question #1011 : Ged Math
What is the circumference of a circle with a diameter of 40?
To find the circumference given the diameter we use the equation:
Then we substitute 40 in for our diameter:
Example Question #7 : Circumference
Find the radius of a circle given that the circumference is .
24
5
16
12
12
The equation of the circumference of a circle is as follows:
Now we substitute in our circumference and solve for radius:
Example Question #46 : Geometry And Graphs
What is the circumference of a circle with a radius of 4?
We use the equation for the circumference of a circle:
Now we substitute in our radius of 4:
Example Question #8 : Circumference
If the area of a circle is , what is its circumference?
Cannot be computed from the information provided
To solve this, you should first figure out your radius. Remember that the area of a circle is defined as:
For your data, you know that this is:
Solving for , you get:
, or
Now, recall that the circumference of a circle is defined as:
For your data, this is:
Example Question #9 : Circumference
The area of a sector of a circle with a degree angle is . What is the circumference of this circle?
Cannot be computed from the information provided
A degree angle represents one fourth of a full circle. Therefore, the total area of this circle is or . Now, recall your area formula:
For your data, this means:
Solving for , you get:
or
Now, the circumference of a circle is defined as:
For your data, this is:
Example Question #51 : Geometry And Graphs
What is the circumference of the circle with an area of 5?
Write the formula for the area of a circle.
Substitute the area.
Divide by pi on both sides.
Square root both sides.
Write the circumference formula for the circle, and substitute the radius.
Since , we can eliminate the denominator by rewriting .
The answer is:
Example Question #11 : Circumference
Find the circumference of a circle with an area of .
Write the formula for the area of a circle, and substitute the area into the formula.
Divide by pi on both sides.
Square root both sides.
Write the formula for the circumference of the circle.
Substitute the radius into the equation.
The answer is:
Example Question #12 : Circumference
Find the circumference of a circle with a diameter of .
Write the formula for the circumference.
Substitute the diameter into the equation.
The answer is:
Example Question #13 : Circumference
Find the circumference of a circle with a diameter of 14cm.
To find the circumference of a circle, we will use the following formula:
where d is the diameter of the circle.
Now, we know the diameter of the circle is 14cm. So, we will substitute. We get
Example Question #51 : Geometry And Graphs
Identify the circumference of the circle with an area of .
Write the formula for the area of a circle.
Substitute the area.
Square root both sides to find the radius.
Write the formula for the circumference of the circle.
The answer is: