What would the area of a circle be if the circumference is 20pi?

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Answer 1 · 2015-08-01T15:34:58

#=color(blue)(314cm^2#

The circumference of a circle is given by formula:
#color(blue)(2pir#

So, #2pir=20pi#

#2cancelpir=20cancelpi#

#r=20/2#

#r=10cm#(assuming the units to be in #cm#)

The area of a circle is given by formula:
#color(blue)(pir^2#

Where,
#pi# has a constant value of #approx3.14#
and #r# denotes the radius.

The radius of the circle #=10cm#

The area #= pir^2 approx 3.14 xx (10)^2#

#=3.14 xx (100)#

#=color(blue)(314cm^2#