How do you find the diameter from a circumference of 20?

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Answer 1 · 2016-01-06T15:50:10

#diameter =6.36 cm#

The circumference of the circle is #=20 cm#
(note: assuming units to be in cm)

The formula for circumference of circle #=2pir#

#r= radius, pi = 22/7#(constant)

#2 pi r = 20#

#2 xx 22/7 xx color(blue)(r) = 20#

# color(blue)(r) = 20 xx 7/22 xx 1/2#

# color(blue)(r) = cancel20 xx 7/22 xx 1/cancel2#

# color(blue)(r) = 10 xx 7/22#

# color(blue)(r) = 70/22#

So the diameter #= 2 xx radius#

#= cancel2 xx 70/cancel22#
#=70/11#

#diameter =6.36 cm#