Pi and Diameter Part 2

Open Ended

What is something that always makes you laugh?

Match

Recall:

Match the following

• Radius

• Diameter

• Chord

• Circumference

• 1/2 of the Diameter

Distance from the center to the edge of a circle

Distance across a circle through its center

Line segment with both endpoints on the circle

Distance around the edge of a circle

Distance from the center to the edge of a circle divided by 2

• Distance from the center to the edge of a circle

• Distance across a circle through its center

• Line segment with both endpoints on the circle

• Distance around the edge of a circle

• Distance from the center to the edge of a circle divided by 2

Circle Circumference and Area

Standard:
MA.7.GR.1.3 Explore the proportional relationship between circumferences and diameters of circles. Apply a formula for the circumference of a circle to solve mathematical and real-world problems.

An important question.

Circumference & Area

Multiple Choice

I Do:

I measured from the center of the wheel to the outside edge and it was 62.2 cm. What is the circumference of the wheel? Use 3.14 for pi.

• 62.2 cm

• 195.308 cm

• 124.4 cm

• 390.616 cm

Multiple Choice

I Do:

Find the circumference of the circle

• 50.24 yd

• 25.12 yd

• 11.14 yd

Multiple Choice

We Do:

I wrapped a tape measure around the trunk of the tree and it was 10 feet. What is the diameter of the tree? Use 3.14 for pi. Round to the nearest hundredth.

• 1.59 ft

• 31.4 ft

• 3.18 ft

• 10.11 ft

Multiple Choice

You Do:

Find the circumference of the circle whose radius is 4 in

• 12.56 in

• 25.12 in

• 50.24 in

Match

Exit Ticket:

Match the following

• Circumference

• Circumference of a plate w/ d=6

• Chord

• Circumference

• 1/2 of the Diameter

C =

18.84

Line segment with both endpoints on the circle

Distance around the edge of a circle

Distance from the center to the edge of a circle divided by 2

• C = $$\pi d$$

• 18.84

• Line segment with both endpoints on the circle

• Distance around the edge of a circle

• Distance from the center to the edge of a circle divided by 2