i got 12, hope that this ans is close and my reasoning is baliddkumar.83 wrote:
(240/360)*2*pi*R=24
R=6, D=12
Circles
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orel
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We need to find the approximate diameter, which is 2R.
Length of the arc ABC=2/3 of the length of circumference.
The length of circumference is measured as 2ПR
24=2/3*2ПR
2ПR=72/2=36
2R=36/3.14=~11
Length of the arc ABC=2/3 of the length of circumference.
The length of circumference is measured as 2ПR
24=2/3*2ПR
2ПR=72/2=36
2R=36/3.14=~11
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clock60
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as all angles of triangle are equal the circle is divided on 3 equal arc ab, bc, ca, and each is equal 360/3=120 degreesdkumar.83 wrote:The correct answer is 11. BTW how did u assumed 240degrees?
so ab+bc=120+120=240
the other way to see that angle abc=1/2* center angle. 60=1/2*center angle. and center angle=120. say aoc=120. then
360-120=240. (i mean external center angle=240)
also i assumed that pi=3 and final answer does`t match exactly
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orel
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dkumar.83 wrote:Hey orel,
How did u assumed that length of d arc is 2/3rd of circumference?
It is an equilateral triangle inscribed into a circle, so it divides the circumference of the circle into 3 equal parts. Arc ABC is 2/3 of the circumference.
