Practice Area of Circles

What formula is this used for:
πr²

• Circumference 

• Area

• Surface Area

• Volume

What is the diameter?

• 8

• 16

• 10

• 4

What is the radius?

• 18

• 72

• 38

• 14

Diameter 32 inches
What is the radius?

• 16 inches

• 64 inches

• 96 inches
  96 inches

• 16 ft 

What is the circumference?

• 36

• 18π

• 108π

• 36π

If my radius is 10ft, what is my diameter?

• 20ft

• 5ft

• 31.4ft

• 62.8ft

What formula is used to find the space 
"inside" a flat object?

• Circumference 

• Surface Area

• Area

• Volume

Find the area of the circle. Round your answer to the nearest hundreth.

• 22 ft ²

• 21.98 ft²

• 153.86 ft²

• 38.465ft²

Find the area of a circle. Round to the nearest tenth.

Find the area of the semicircle. Round your answer the nearest hundredth.