Question

Umference of a Circle: Mastery Test

S
Drag the tiles to the correct boxes to complete the pairs. Not all tiles will be used
Match each circumference to the corresponding radius or diameter of the circle. (All circumferences are approximate.)
circumference: 34.54 units
circumference: 59,66 units
circumference: 23.236 units
circumference: 26.376 units
circumference: 13.188 units
circumference: 29,83 units
radius: 4.2 units
diameter: 7.4 units
diameter: 11 units

Answer 1

•26.376 units

•23.236 units

•34.54 units

•59.66 units

Explanation:

The formula for the circumference of a circle is ...

C = 2πr = πd

C = 2(3.14)r = 6.28r or C = 3.14d

where r is the radius and d is the diameter.

Put the given radius or diameter into the relevant formula and compute the product. The results are all in "units".

r = 4.2 ⇒ C = 6.28×4.2 = 26.376

d = 7.4 ⇒ C = 3.14×7.4 = 23.236

d = 11 ⇒ C = 3.14×11 = 34.54

r = 9.5 ⇒ C = 6.28×9.5 = 59.66