SOLUTION: The length of an arc of circle subtending an angle of measure 60* at the centre is 10cm. Find the area and the circumference of the circle.

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Question 982055: The length of an arc of circle subtending an angle of measure 60* at the centre is 10cm. Find the area and the circumference of the circle.
Found 2 solutions by macston, josgarithmetic:
Answer by macston(5194) About Me  (Show Source):
You can put this solution on YOUR website!
.
Is 60*=60 degrees?
If not, disregard and re-post.
%28360degrees%29%2F%2860degrees%29=x%2F10cm Cross multiply
3600cm_degrees=%2860degrees%29x
%283600cm_degrees%29%2F60degrees=x
60cm=x ANSWER 1: Circumference is 60cm
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Circumference=diameter(pi)
Circumference/pi=diameter
60cm/pi=diameter
19.1cm=diameter
r=radius=19.1cm/2=9.55cm
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Area=(pi)r^2
Area=(pi)(9.55cm)^2
Area=(91.19)(pi)cm^2

Answer by josgarithmetic(39618) About Me  (Show Source):
You can put this solution on YOUR website!
2pi%2Ar, whole circumerence;

The specified fraction of the circumference, 60%2F360=1%2F6.

%281%2F6%29%282pi%2Ar%29=10
Solve for r, and you can then compute area of the circle and the circumference.

pi%2Ar%2F3=10
pi%2Ar=30
highlight_green%28r=30%2Fpi%29