Circumference and Area of Circles

Math STAAR Bootcamp

7.9(B) determine the circumference and area of circles

Multiple Choice

Is the red line a radius or diameter of the circle?

• Radius

• Diameter

Multiple Choice

Is the red line a radius or diameter of the circle?

• Radius

• Diameter

Multiple Choice

Is the red line a radius or diameter of the circle?

• Radius

• Diameter

Multiple Choice

Is the red line a radius or diameter of the circle?

• Radius

• Diameter

Multiple Choice

What is this symbol called?

• pi

• sigma

• radius

• omega

Drag and Drop

The radius of a circle is ​

Placeholder

the diameter.

Drag these tiles and drop them in the correct blank above

half

twice

triple

Drag and Drop

The diameter is ​

Placeholder

so the radius of the circle is ​

Placeholder

Drag these tiles and drop them in the correct blank above

8 inches

4 inches

16 inches

2 inches

Drag and Drop

If the diameter of a circle is ​

Placeholder

, the radius is ​

Placeholder

.

Drag these tiles and drop them in the correct blank above

10 cm

5 cm

20 cm

2 cm

2.5 cm

Drag and Drop

The diameter of this circle is ​

Placeholder

so the radius is ​

Placeholder

.

Drag these tiles and drop them in the correct blank above

16 km

8 km

32 km

4 km

​Write down formulas!!!

Multiple Choice

Find the circumference (to the nearest whole number)

• 88 in
• 44 in
• 116 square in
• None of the above

Multiple Choice

What is the circumference?

• 50.24
• 96
• 24
• 18

Multiple Choice

what is the circumference of this circle ?

• 3.14 cm 
• 37.68 cm
• 24 cm
• 68.4 cm

​https://youtu.be/KZW9b_LJkMk?si=-FR4yq6d74opJppr

​Write down formula!!!

Multiple Choice

Find the area of the circle

• 43.96
• 153.86
• 87.82
• 307.72

Multiple Choice

find the area of the circle below.

• 100 cm
• 225 cm
• 9 cm
• 28.26 cm

Multiple Choice

What is the area of this circle?

• 15393.8
• 1248.12
• 5930.12
• 3848.45

Multiple Choice

Find the area of the circle

• 56.52
• 254.34
• 1017.36
• 113.04

Multiple Choice

find the area of the circle below.

• 100 cm
• 225 cm
• 9 cm
• 28.26 cm