Circle Jeopardy

Solving Circles

100

Draw the shape that represents pi?

π

200

What is the name of the line that passes through the center of a circle and has both endpoints on the perimeter of a circle?

Diameter

300

What is the name of the line that has one endpoint in the center of a circle, and the other on the perimeter?

Radius

400

What formula do you need the diameter for?

Circumference, πd

500

What measure of a circle do you find with the radius?

Area, πr²

Calculating Circumference

100

What is the circumference of a circle with a diameter of 5 inches?

15.7 inches

200

What is the circumference of a circle with a radius of 7 inches?

43.96 inches

300

What is the diameter of a circle that has a circumference of 28.26 feet?

9 feet

400

How do you find the radius if you are given the circumference of a circle?

Divide the circumference by 3.14, then divide the answer by 2.

500

What is the radius of a circle that has a circumference of 18.84 centimeters?

3 centimeters

Calculating Area

100

What is the area of a circle with a radius of 2 inches?

12.56 inches²

200

What is the area of a circle with a diameter of 18 feet?

254.34 feet²

300

What is the radius of a circle that has an area of 615.44 feet² ?

14 feet

400

How do you find the diameter of a circle if you are given the area?

Divide the area by 3.14, then take the square root of the number that remains. Finally multiply the number by 2.

500

What is the diameter of a circle that has an area of 200.96 centimeters² ?

16 centimeters

Parts of a Circle

100

What is the measure of the inside of a circle called, and what equation is used to find it?

Area, πr²

200

What is the measure of the outside of a circle called, and what equation do you use to find it?

Circumference, πd

300

What is the radius of a circle whose diameter is 10 centimeters?

5 centimeters 

400

What is the diameter of a circle whose radius is 7 miles?

14 miles

500

What is the radius of a circle whose diameter is 27 inches?

13.5 inches

Story Problems

100

You want to figure out how wide a tree is, and know that you can find its diameter if you know the circumference. You measure the circumference, and find out it is 18.84 feet. What is the diameter?

6 feet

200

An asteroid hit the earth and created a huge round crater. Scientists measured the distance around the crater as 78.5 miles. What is the diameter of the crater?

25 miles

300

The distance around a carousel is 21.98 yards. What is the radius?

3.5 yards

400

A semi-circle shaped rug has a diameter of 4 feet. What is the area of the rug?

6.28 feet²

500

You order a pizza with a diameter of 14 inches. You eat 1/4 of the pizza, so there is 3/4 left. What is the area of the pizza that remains?

115.395 inches²