## Question-Arc for Equilateral

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### Question-Arc for Equilateral

by cubicle_bound_misfit » Sat Aug 01, 2009 4:33 am
Hi,

My idea was that 120/360 * 2*pi*r = 24.

Let me know where I am wrong.
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by pandeyvineet24 » Sat Aug 01, 2009 4:57 am
actually it should be 240/360 (of circle perimeter) = 24. Since each of the angles of equilateral are 60 degrees. then angle ABC = 240 degrees

perimeter = 36

2 * pi * r = 36 gives D = 11 (approx)

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by truplayer256 » Sat Aug 01, 2009 5:00 am
Measure of Arc AC-120 degrees

Measure of Arc ABC-360-120=240 degrees

C=Pi*d

Pi*d*2/3=24

24*3/2=Pi*d

36/pi=d

36/3.14~11

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by maihuna » Sat Aug 01, 2009 5:06 am
Given ABC arc = 24

=>One arc following AB will be 12

Given angle at circumference is 60 angle at centre will be 120

So the circumference = arc of 360 = 3*arc corresponding 120 = 3*12=36

=>II.D = 36 or D = 36/3.14 = 11
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by cubicle_bound_misfit » Sat Aug 01, 2009 5:46 am
how to understand ABC is a major arc ???
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by mohitsharda » Sat Aug 01, 2009 6:06 am
It is the major arc bcoz it says ABC so you have to from A to B to C... otherwise it would have been ACB, for it to be the minor arc
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by cubicle_bound_misfit » Sat Aug 01, 2009 9:15 am
Mohit ,
Thanks a bunch
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