Circumference and Parts of a Circle

Area and Circumference of a Circle

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Parts of a Circle

• Radius: line segment that goes from the center to the edge of the circle (HALF the DIAMETER)

• Diameter: line segment that goes from edge to edge on a circle (TWICE the RADIUS)

• Circumference: the distance around the outside of a circle (AKA perimeter)

Area of a Circle

Area is the space inside of the circle.

Fill in the Blanks

The diameter of a circle is 10 ft. Find its area to the nearest tenth.

Fill in the Blanks

The diameter of a circle is 14 ft. Find its area to the nearest tenth.

Circumference

Unlike area, there are two formulas that can be used to find the circumference of a circle:

One when given the diameter

and

One when given the radius.

Fill in the Blanks

The radius of a circle is 5.3 ft. Find the circumference to the

nearest tenth.

Fill in the Blanks

The diameter of a circle is 13 in. Find the circumference to

the nearest tenth.

Delta Math

Area of a Circle (rounded)

Circumference (rounding)