3. Break the problem into bite-sized pieces. We know we need an equation that will work for all
the points in this chart. Let’s pick one set of points that will be easy to test, and then a second set to
confirm our answers. Go easy on yourself! There’s no reason to pick the biggest numbers. Let’s try
first the point to the far right of the chart: d = 9, f = 0. We want an equation that will work for these
points, so let’s try the answers:
F. 0 = 9 − 9
G. 0 = 3(9 − 9)
H. 0 = 3(9) + 3 ×
J. 0 = 3(36 − 4(9))
K. 0 = 96(9)
Okay, we’ve eliminated two of the answer choices. Now let’s try another set of points: d = 7, f = 24.
F. 24 = 9 − 7 ×
G. 24 = 3(9 − 7) ×
H. f = 3d + 3
J. 24 = 3(36 − 4(7))
K. f = 96d
Only one remains, and our best answer is (J). All using basic arithmetic in the formulas provided.
PLUGGING IN THE ANSWERS
Now, what happens when we don’t have the hallmarks of easy Plugging In problems: variables in the
answer choices or in the problem? Like question 45:
- A high-school basketball player has shot 170 free throws and has made 100 of those free throws. Starting now, if
she makes each free throw she attempts, what is the least number of free throws she must attempt in order to
raise her free-throw percentage to at least 70% ?
A. 19
B. 20
C. 63
D. 64
E. 70
In this problem, there are no variables anywhere to be seen. Still, we’re going to need to put together
some kind of equation or something that will enable us to answer the question. For this one, we can Plug
in the Answers (PITA).