math  grade 7
posted by deb .
determine the diameter of a circle with a radius of 4.26m.
determine the area of the circle with diameter is 8mm.

d = 2 r
d = 2 * 4.26 = 8.52 m
A = d ^ 2 pi / 4
A = 8 ^ 2 pi / 4
A = 64 pi / 4
A = 16 pi mm ^ 2
A = 16 * 3.14 = 50.24 mm ^ 2
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