Cracking The SAT Premium

27. π radians is approximately equal to how many degrees?

A) 8°

B) 694°

C) 1,389°

D) 2,777°

Here’s How to Crack It

Use the relationship between radians and degrees to set up a proportion. If 180 degrees = π radians, then
the proportion will look like the following:

Cross-multiply to get 180 × π = πx. Divide both sides by π:180 × = x. Finally, use your calculator,

and you find that x is approximately 1,389, which is (C).

Triangles

Here are some basic triangle rules you’ll need to know for the SAT.

1. Every triangle contains 180 degrees.
   The word triangle means “three angles,” and every triangle contains three interior angles. The
   measure of these three angles always adds up to exactly 180 degrees. You don’t need to know
   why this is true or how to prove it. You just need to know it. And we mean know it.


2. An isosceles triangle is one in which two of the sides are equal in length.