Target 2: Calculating circumference of a circle

Which equation would solve for the circumference of the given circle?

• 4.5 x 3.14

• 9 x 3.14

• 9/3.14

• 4.5 x 2

The circumference of a circle is...

• The distance around the circle

• The amount of space inside the circle

• Pi

• The distance across the circle

Given the radius of a circle, how would you calculate the diameter?

• Divide the radius by 2

• Multiply the radius by pi

• Multiply the radius by 2

• Divide the radius by pi

Calculate the circumference.

• 3.14 x 32 = 100.48 m

• 64 / 3.14 = 20.38 m

• 3.14 x 128 = 401.92 m

• 3.14 x 64 = 200.96 m

The circumference of a circle is 18.41 feet. What is the length of the diameter?

• 57.81 feet

• 2.93 feet

• 5.86 feet

• There is not enough information to solve for the diameter of the circle.

The radius of a birthday cake is 5 inches. Icing will decorate the circumference of the cake. What procedure can be used to find the approximate circumference of the cake?

• Multiply 5 by 3.14.

• Multiply 5 by 2 and the product by 3.14.

• Multiply 5 by 5 and the product by 3.14.

• Multiply 5 by 3 and the product by 3.14.

What is the approximate circumference of the given circle?

• Approximately 15 inches

• Approximately 10 inches

• Approximately 25 inches

• Approximately 5 inches

Dawn bought a circular rug. The radius of the rug was 3 feet. How does the diameter of the rug compare to the radius?

• The diameter of the rug is twice the radius.

• The diameter of the rug is half the radius.

• The radius is twice the circumference.

• The radius is 3.14 times the diameter.

Calculate the radius of the given circle.

• 12.4 mm

• 3.1 ft

• 19.47 mm

• 3.1 mm

Calculate the circumference of the given circle.

• 19.47 mm

• 3.1 mm

• 12.4 mm

• 9.73 mm