You’ll be given this information in your test booklet, so don’t stress over memorizing these
formulas. You will always be able to refer to your test booklet if you forget them. Just keep in
mind that the diameter is always twice the length of the radius (and that the radius is half the
diameter).A Few Formulas
Area = πr^2
Circumference = 2πr or πd
Diameter = 2rIn math class you probably learned that π = 3.14 (or even 3.14159). On the SAT, π = 3+ (a little more than
3) is a good enough approximation. Even with a calculator, using π = 3 will give you all the information
you need to solve difficult SAT multiple-choice geometry questions.
Leave That π Alone!
Most of the time, you