SAT Mathematics Practice Test 4

Since the radius of the circle is 10, its circumference is $20\mathit{\pi }$. The full circumference of a circle is $360°$. Thus, an arc of length s on the circle corresponds to a central angle of $\mathit{x}°$, where $\frac{\mathit{x}}{360}=\frac{\mathit{s}}{20\mathit{\pi }}$, or $\mathit{x}=\frac{360}{20\mathit{\pi }}\mathit{s}$.Since ,it follows that which becomes, to the nearest tenth, . Therefore, the possible integer values of x are $29,30,31,32,33,$ and $34$. Any one of these numbers may be gridded as the correct answer.