Cracking The SAT Premium

the polygon into    triangles.

Let’s try an example:

12.

Note:   Figure  not drawn   to  scale.

In  parallelogram   ABCD    above,  AC  =   3   and AD  =   5.  What    is  the area    of  ABCD    ?

A) 12

B) 15

C) 18

D) 20

Here’s How to Crack It

The trick is to notice that this parallelogram is actually made of two equal triangles. By finding the area of
the triangles, you can find the area of the parallelogram. The triangles are both right triangles, and the two
sides given in the figure follow the 3-4-5 pattern. If you look at triangle ACD with AC as the base, the
base is 3 and the height is 4. Now use the formula for area of a triangle:

A   =       ×   3   ×   4   =   6

That means the parallelogram is 2 × 6 = 12.

Also, if you estimate the area, the base is 5 and the height is less than 3, so the area is less than 15. The
only answer less than 15 is (A).

Volume

Volume questions on the SAT can seem intimidating at times. The test writers love to give you questions
featuring unusual shapes such as pyramids and spheres. Luckily, at the beginning of the Math sections (and
the beginning of this chapter), you’re given a box with all the formulas you will ever need for volume
questions on the SAT. Simply apply the Basic Approach using the given formulas and you’ll be in good