SAT Subject Test Mathematics Level 2

(Marvins-Underground-K-12) #1
You also    could   Pick    Numbers on  this    problem.    Choose  a   value   for x   and then    find    the volume
and the value of d. Plug d into the answer choices and see which one matches.

3 . D
When a cube of edge length b is divided into 8 identical smaller cubes, the edge of each of
the smaller cubes is .


The surface area    of  the original    cube    is  6   ×   b   ×   b   =   6b^2 .  The surface area    of  one of  the smaller
cubes is

or   .  There   are eight   small   cubes,  so  their   combined    surface area    is   .  The
difference is 12b^2 – 6b^2 = 6b^2.

4 . D
When you write the equations for the volumes, try to plug in the area of the triangle, since
that is known.


When    you rotate  a   right   triangle    about   a   leg,    you get a   cone:

One leg becomes the base    radius, and the other   becomes the height  of  the cone.   Call    the
short leg a and the long leg b and plug them into the cone volume formula:

It’s    also    given   that    the area    of  the right   triangle    is  4.  Therefore,
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