All Pre-Algebra Resources
Example Questions
Example Question #1 : Perimeter
Becky's house is surrounded by a circular lake that Becky runs around each day. If Becky wants to figure out the distance she runs around the lake, what formula should Becky use?
None of the other answers
Becky should use the circumfrence formula to find the distance she runs of a lake.
Correct Answer:
Example Question #2 : Perimeter
What is the circumference of a circle with an area equal to ?
Using the area, solve for the radius:
Divide by :
Take the square root:
Plug this radius into the formula for the circumference:
Example Question #1 : Circumference Of A Circle
What is the circumference of a circle with a radius equal to ?
The circumference can be solved using the following equation:
Example Question #2 : Circumference Of A Circle
What is the circumference of a circle with a radius of ?
The circumference can be solved using the following equation:
Where represents the radius. Therefore, when we substitute our radius in we get:
Example Question #1 : Know And Use The Formulas For The Area And Circumference Of A Circle: Ccss.Math.Content.7.G.B.4
The perimeter of a given rectangle is equal to the circumference of a given circle. The circle has radius inches; the width of the rectangle is inches. What is the length of the rectangle?
inches
inches
inches
inches
inches
inches
The circumference of a circle with radius inches is
inches.
The perimeter of the rectangle is therefore inches. To find its length, substitute and into the equation and solve for :
inches
Example Question #2 : Perimeter
Determine the circumference of the circle if the radius is 20.
Write the formula for circumference.
Substitute the radius and solve.
Example Question #3 : Perimeter
Given the area of the circle is , what is the circumference of the circle?
Write the formula for the area of a circle.
Substitute the area.
Write the circumference of the circle.
Substitute the radius.
Example Question #4 : Perimeter
Find the circumference of a circle with an area of .
Write the area formula in order to find the radius.
Substitute the area.
Write the circumference formula.
Substitute the radius.
Example Question #5 : Perimeter
Determine the circumference of the circle if the radius is .
Write the formula for the circumference of a circle.
Substitute the radius into the formula.
Example Question #6 : Perimeter
Find the circumference of a circle with a radius of .
Write the formula to find the circumference of a circle.
Substitute the radius.
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