The Princeton Review - Princeton Review PSAT 8_9 Prep-Random House Children's Books (2021)

plug in some numbers for d. Plug in d = 1, d = 2, and d = 3
to see what happens over time.
d = 1 d = 2 d = 3
For Intersection X: t = 450(1) =
450
For Intersection Y: t = 150(1) =
150
450(2) = 900 450(3) = 1,350
150(2) = 300 150(3) = 450
12. B
Each hour, the number of cars passing through
Intersection X increases by 450, and the number of cars
passing through Intersection Y increases by 150. Therefore,
for either intersection, the rate is constant and not
increasing at all for either intersection. Eliminate (A) and
(C), since both refer to an increasing rate. Compare the
remaining answers. The only difference is whether the
number of cars passing through Intersection X or
Intersection Y is greater. Choice (D) says that the number
of cars passing through Intersection Y is greater, which is
not true. Intersection X has greater numbers at all values of
d, so eliminate (D). The correct answer is (B).
The question asks for an equation in terms of a specific
variable. Although there are variables in the answer
choices, plugging in on this question would be difficult
given the number of variables. Instead, solve for n. To
begin to isolate n, multiply both sides of the equation by n
to get np = m. Divide both sides by p to get
. The