Question

In a circle of diameter 40cm the lenght of a chord is 20cm. Find the length of the major arc corresponding to the chord.

Answer 1

[(100pi)/3] cm?

Answer 2

@eliassaab A minor mistake
\[2\Pi-(\Pi/3)=5\Pi/3\]

Answer 3

Old age. I do not know how to subtractt anymmore.

Answer 4

Ha Ha... happens

Answer 5

Thanks for @scsam here is a correction;
The circle formed by the center in the two endpoints of the chord is equilateral. So the small arc is

\[
\frac \pi 3
\]

and the big chord is
\[
2\pi -\frac \pi 3 = \frac{5\pi} 3
\]
So the length of it is
\[20 \frac{5\pi} 3 =\frac {100 \pi}{3}

\]