Area and Circumference of Circles

Front

If my diameter is 19 inches, what is my radius?

Back

9.5 inches

Front

If my radius is 10ft, what is my diameter?

Back

20ft

Front

What is the circumference of this circle?

Back

37.68 cm

Front

Circumference of a circle with radius 12.5 mm

Back

78.5mm

Front

The radius of a circle is

Back

The measurement from the center of a circle to an edge of the circle.

Front

What is the formula for finding the circumference for a circle with just the radius?

Back

2*π*r

Front

What is the formula for finding the circumference of a circle with just the diameter?

Back

π*d

Front

A cruise ship has a large, circular window with a diameter of 6 meters. What is the window's area?

Back

28.26 m²

Front

Does this picture show the diameter or radius of a circle?

Back

Radius

Front

Is the red line a radius or diameter of the circle?

Back

Diameter