Circumference and Area

Front

What is the formula for calculating the circumference of a circle?

Back

C = π·d, where C is the circumference and d is the diameter.

Tags

CCSS.7.G.B.4

Front

What does the symbol π (pi) represent?

Back

π (pi) is approximately equal to 3.14 and represents the ratio of the circumference of a circle to its diameter.

Tags

CCSS.HSG.GMD.A.1

Front

If the diameter of a circle is 10 cm, what is its circumference?

Back

C = π·d = 3.14·10 = 31.4 cm.

Tags

CCSS.7.G.B.4

Front

What is the area of a circle with a radius of 7 cm?

Back

Area = π·r² = 3.14·(7)² = 153.86 cm².

Tags

CCSS.7.G.B.4

Front

What does 'C' represent in the formula C = π·d?

Back

C represents the circumference of the circle.

Tags

CCSS.HSG.C.B.5

Front

How do you find the radius of a circle if you know the circumference?

Back

Radius = C / (2·π).

Tags

CCSS.7.G.B.4

Front

What is the relationship between diameter and radius?

Back

The diameter is twice the radius (d = 2·r).

Tags

CCSS.7.G.B.4

Front

If the circumference of a circle is 62.8 cm, what is the diameter?

Back

Diameter = C / π = 62.8 / 3.14 = 20 cm.

Tags

CCSS.7.G.B.4

Front

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

Back

Area = π·(d/2)² = π·(5)² = 78.5 cm².

Tags

CCSS.7.G.B.4

Front

What is the circumference of a circle with a radius of 4 cm?

Back

C = 2·π·r = 2·3.14·4 = 25.12 cm.

Tags

CCSS.7.G.B.4