Because we do not have all the information we need, we can plug in values that we know must be true.

We know that we already have 75 Documentary DVDs in stock, plus $x$ to be added. So we have a total of $75+x$ Documentary DVDs.

Next, we know that this value is less than or equal to $5 \%$ of the total. Now we can set up an equation to better visualize this:

(Total DVDs) $(\(5\) %)\( \geq 75^{\prime \prime}+x\)$

Then change 5% into 0.05

(Total DVDs) $\((0.05) \geq 75+x\)$

Now we can plug in the answer choices, which are potential total DVD numbers, into our equation.

(A) $\((1,400)(0,05)=70\)$

$$
\(\begin{aligned}
70 & \geq 75+x \\
x & \leq-5
\end{aligned}\)
$$


This is incorrect; we can't have a negative shipment of DVDs. The value has to be at least 1.

(B) $\((1,480)(0.05)=74\)$

$$
\(\begin{aligned}
74 & \geq 75+x \\
x & \leq-1
\end{aligned}\)
$$

This is incorrect for the same reason as (A).

(C) $\((1,500)(0.05)=75\)$

$$
\(\begin{aligned}
75 & \geq 75+x \\
x & \leq 0
\end{aligned}\)
$$


This is incorrect: we know the store received at least 1 new DVD.

(D) $\((1,520)(0.05)=76\)$

$$
\(\begin{aligned}
76 & \geq 75+x \\
x & \leq 1
\end{aligned}\)
$$


This is correct; the store could possibly have received a shipment of 1 Documentary DVD.
Thus, (D) is our correct answer.
13. D

In order to solve, we must find the percentage of 513 out of 2,700:

$$
\(\frac{513}{2,700}=0.19\)
$$


However, we want more than 513, or more than 19%.
Answer choice ( $D$ ) is more than $19 %$. Comedy, which is exactly $19 %$, is not eligible.
The correct answer is (D).