SOLUTION: if a circle and a square have the same area of any number, what would be the circles perimeter?

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Question 964970: if a circle and a square have the same area of any number, what would be the circles perimeter?
Answer by rothauserc(4718) About Me  (Show Source):
You can put this solution on YOUR website!
let the area of the circle and the square have area 25, then
Area(A) of circle = pi*r^2 where r is the radius,
25 = pi*r^2
r^2 = 25 / pi
r = sqrt(25 / pi) = 5*sqrt(1/pi)
note the diameter(d) of a circle = 2*r
d = 2*5*sqrt(1/pi) = 10*sqrt(1/pi)
circumference(c) of circle = pi*d, where d is the diameter
c = pi * 10 * sqrt(1/pi)
note using pi = 3.14
c = 3.14 * 10 * sqrt(1/3.14) = 17.720045147 approx 17.72