Area of Circles, Semi-Circles, and Composite Figures

A (a)   is half of a circle.

• circumference
• pi
• semicircle
• composite figure

How do you find the area of a circle?

Tags

CCSS.7.G.B.4

If you are given the diameter, how can you calculate the radius?

• Multiply the diameter by 2

• Subtract 2 from the diameter

• Add 2 to the diameter

• Divide the diameter by 2

Tags

CCSS.7.G.B.4

A circular swimming pool is 21 feet in diameter.

How many square feet is the area of the pool?

• 693 ft²

• 346.5 ft

• 65.94 ft²

• 346.2 ft²

Tags

CCSS.7.G.B.4

Find the area.

• 34.54 cm²

• 379.94 cm²

• 189.97 cm²

• 44.54 cm²

Tags

CCSS.7.G.B.4

Find the area.

• 25.12 m²

• 50.24 m²

• 12.56 m²

• 20.56 m²

Tags

CCSS.7.G.B.4

Randy’s circular garden has a radius of 1.5 feet. He wants to enclose the garden edging that costs $0.75 per foot. About how much will the edging cost? 

• $8.00
• $7.00
• $3.50
• $0.50

Tags

CCSS.7.G.B.4

 A glass stained window is shaped like a semicircle. The bottom edge of the window is 36 inches long. How much colored glass would you need to cover the stained window? Round to the nearest hundredth.

• 1017.36 in²
• 508.68 in²
• 56.52 in
• 113.04 in

Tags

CCSS.7.G.B.4

A circular pie has an area of 706.5 cm². What is the radius of the pie?

• 225 cm
• 30 cm
• 15 cm
• 112.5 cm

Tags

CCSS.7.G.B.4

The diameter of the face-off circle on an ice-hockey rink is 30 feet. Find its area.

• 675.6 ft^2

• 29.67 ft^2

• 545.8 ft^2

• 706.5 ft^2

Tags

CCSS.7.G.B.4