Measuring Circles

What is the correct formula for AREA of a circle?

• 3.14 X 3.14

• Pi X r²

• Pi X Diameter

• Pi X d²

To find the circumference of a circle, multiply Pi and the ___________________.

The radius is _____ of the diameter.

• 2 times

• 1/3

• 1/4

• 1/2

The approximation we use for the irrational number Pi is...

• 3.14

• 2.14

• 4.31

• 18.2

The diameter of this semicircle is 18. What is the area?

• 254.34

• 127.17

• 1,017.36

• 56.52

What is the area of this shape? Hint: find the area of the squares then the semicircles

• 362

• 1920

• 94.2

• 614

Which of the following is a situation in which we would need to calculate circumference?

• The amount of oil it takes to cover a circular frying pan.

• The amount of frosting to put on a circular cake.

• The amount of space a circular rug takes up.

• The distance around a circular pool.

What is the PERIMETER of a semicircle with a diameter of 12. Hint: Draw it out.

• 37.68

• 30.84

• 18.84

• 113.04

If K is the center of the circle, which line segment is the radius?

• KN

• JM

• ML

• JL

Line Segment _________ represents the diameter?