Area and Circumference - Review

Formulas

100

What is the formula for the area of a rectangle?

A = l x w

200

What is the formula for the area of a triangle?

A = (b x h)/2

300

What is the formula for area of a circle?

A = pi x r²

400

What is the formula for the circumference of a circle?

C = pi x d

500

What is the formula for the volume of a rectangular prism?

V = Area of base x height of the prism

(V = l x w x h)

Circumference (Use 3.14 for pi)

100

Find the circumference of a circle with a diameter of 19 feet.

C = 59.66 feet

200

Find the circumference of a circle with a radius of 3mm

C = 18.84 mm

300

What is the circumference of a circle with a radius of 17 inches?

106.76 inches

400

Randy is designing a circular garden that is 18 feet in diameter. He is buying plastic edging that costs $1.50 per foot. He can only buy whole-foot amounts. How much does it cost Randy to buy edging for his garden?

$85.50

500

What is the radius of a circle with a diameter of 219.8 square meters?

35m

Area (Use 3.14 for pi)

100

What is the area of a circle with a radius of 3mm?

28.26 mm²

200

What is the area of a circle with a diameter of 10 inches?

78.5 in²

300

A disk is shaped like a flat circular plate. Its radius is 4.25 inches. To the nearest hundredth, what is the area of the disk?

56.72 in²

400

A classmate states that is the radius of a circle is doubled, then its area is doubled. Do you agree or disagree? Why?

Disagree, because radius is multiplied by itself not by 2 (or doubled) when finding area.

500

A carpenter cuts a circle out of a piece of wood. The radius of the circle is about 23 inches. The carpenter cuts the circle into two semicircles. What is the area of the semicircle?

830.53 in²

Cross-sections

100

What shape do you get if you take the cross section of a cylinder parallel to its base?

circle

200

What shape do you get if you take the cross section of a triangular prism parallel to its base?

triangle

300

What shape do you get if you take the cross section of a cone perpendicular to its base?

triangle

400

What shape do you get if you take the cross section of a sphere?

circle

500

What shape do you get if you take the cross section of a cylinder perpendicular to its base?

rectangle

Composite Figures

100

Find the area of the figure: #5 on WS

140 ft²

200

Find the area of the figure:

#7 on WS

100 ft²

300

Find the area of the figure:

#8 on WS

33.28 m²

400

Find the area of the figure: #6 on WS

23.13 m²

500

#9 on WS

57.12 m²