Answer :
[tex]\theta=\frac{\pi}{4}[/tex]
1) Notice that the length of an arc is given by the following formula:
[tex]L=\theta\cdot r[/tex]2) Notice that this is the formula in radians. Now, we can plug into that the given data:
[tex]\begin{gathered} 6\pi=\theta\cdot24 \\ 24\theta=6\pi \\ \frac{24θ}{24}=\frac{6\pi}{24} \\ \theta=\frac{\pi}{4} \end{gathered}[/tex]Therefore, this is the answer.