Area and Circumference

Front

What is the formula for the circumference of a circle?

Back

Circumference = π × diameter (C = πd) or Circumference = 2 × π × radius (C = 2πr)

Front

What is the relationship between diameter and radius?

Back

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

Front

How do you calculate the area of a circle?

Back

Area = π × radius² (A = πr²).

Front

What is the value of π (pi) approximately?

Back

π (pi) is approximately 3.14.

Front

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

Back

Circumference = π × diameter = 3.14 × 10 cm = 31.4 cm.

Front

If a circle has a radius of 5 cm, what is its area?

Back

Area = π × radius² = 3.14 × (5 cm)² = 78.5 cm².

Front

What is the formula for the area of a rectangle?

Back

Area = length × width.

Front

What is the formula for the circumference of a circle if the radius is known?

Back

Circumference = 2 × π × radius (C = 2πr).

Front

What is the diameter of a circle with a circumference of 31.4 cm?

Back

Diameter = Circumference / π = 31.4 cm / 3.14 = 10 cm.

Front

What is a markup in pricing?

Back

Markup is the amount added to the cost price of goods to cover overhead and profit.