Area and Circumference

Front

What is the definition of a circle?

Back

A circle is a shape consisting of all points in a plane that are a fixed distance from a center point.

Front

What is the formula for the circumference of a circle?

Back

Circumference = 2πr or Circumference = πd, where r is the radius and d is the diameter.

Tags

CCSS.7.G.B.4

Front

What is the relationship between diameter and radius?

Back

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

Tags

CCSS.7.G.B.4

Front

What does π (pi) represent?

Back

π (pi) is a mathematical constant approximately equal to 3.14, representing the ratio of the circumference of a circle to its diameter.

Tags

CCSS.HSG.GMD.A.1

Front

How do you calculate the area of a circle?

Back

Area = πr², where r is the radius.

Tags

CCSS.7.G.B.4

Front

What is the diameter of a circle?

Back

The diameter is a line segment that passes through the center of the circle and has its endpoints on the circle.

Tags

CCSS.HSG.C.A.2

Front

What is the radius of a circle?

Back

The radius is the distance from the center of the circle to any point on the circle.

Front

If the radius of a circle is 10 cm, what is the area?

Back

Area = π(10)² = 314 cm² (approximately).

Tags

CCSS.7.G.B.4

Front

If the circumference of a circle is 31.4 cm, what is the radius?

Back

Radius = Circumference / (2π) = 31.4 / (2π) = 5 cm.

Tags

CCSS.7.G.B.4

Front

What is the formula to find the diameter if you know the circumference?

Back

Diameter = Circumference / π.

Tags

CCSS.7.G.B.4