SAT Mathematics Practice Test 4

Since the radius of the circle is 10, its circumference is 20π. The full circumference of a circle is 360°. Thus, an arc of length s on the circle corresponds to a central angle of x°, where

x

360

=

s

20π

, or x=

360

20π

s.Since 5<s<6,it follows that

360

20π

(5)<x<

360

20π

(6)which becomes, to the nearest tenth, 28.6<x<34.4. 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.