Open Up Resources Unit 3 Test Review

Front

What is the formula for the circumference of a circle?

Back

C = 2πr, where C is the circumference and r is the radius.

Front

How do you calculate the radius of a circle if you know the diameter?

Back

The radius is half of the diameter. r = d/2.

Front

What is the relationship between the diameter and circumference of a circle?

Back

The circumference is π times the diameter. C = πd.

Front

What is the formula for the area of a circle?

Back

A = πr², where A is the area and r is the radius.

Front

If the radius of a circle is 9 meters, what is its circumference?

Back

The circumference is approximately 56.52 meters.

Front

What is the area of a circle with a radius of 4.5 feet?

Back

The area is approximately 63.585 ft².

Front

What does π represent in circle formulas?

Back

π (pi) is a mathematical constant approximately equal to 3.14159.

Front

How do you convert from diameter to radius?

Back

Divide the diameter by 2.

Front

What is the circumference of a circle with a diameter of 10 mm?

Back

The circumference is approximately 31.4 mm.

Front

What is the significance of the formula πr²?

Back

It is used to calculate the area of a circle.