CIRCUMFERENCE OF A CIRCLE
You now know that π = Circumference or π = _C_
Diameter
D
Using simple algebra, you will find that the formula can be written C = π D or
Circumference = π x Diameter
Find the length of the circumference of a circle when the diameter is equal to 2
inches.
C = D π D
C = 3.14 x 2 inches
C = 6.28 inches
In this problem we simply substituted in the formula C = π D and solved by
multiplying.
You solve these problems:
(1) Find the circumference of a circle when the diameter equals 10 inches.
C = π D
(2) Find the circumference when the diameter equals 7 inches.
(3) Find the diameter when the circumference equals 6.2832 feet.
D = _C_
π
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