Adriana opens her own book store. She sells a hard cover book for $18 and a paperback for $8. Comic books cost $6.50. Adriana's goal is to earn no less than $50. How many comic books must she sell?

That depends upon what she paid for these books.

Does she want to make at least $50 from selling only comic books?

To determine how many comic books Adriana must sell in order to meet her goal of earning at least $50, we need to set up an equation and solve for the number of comic books.

Let's assume Adriana sells x comic books.

The total revenue from selling the hardcover books would be 18 dollars multiplied by the number of hardcover books sold. Since we don't have information about the number of hardcover books she sells, we'll represent it as y.

Similarly, the total revenue from selling the paperback books would be 8 dollars multiplied by the number of paperback books sold, represented as z.

Finally, the total revenue from selling the comic books would be 6.50 dollars multiplied by the number of comic books sold, represented as x.

Since Adriana's goal is to earn no less than $50, we can write the equation as follows:
18y + 8z + 6.50x ≥ 50

Now, let's gather some additional information. We know that y + z + x is the total number of books sold in the bookstore, but we don't have the specific value. However, we can express this as an inequality since Adriana must sell more than zero books to have a functioning bookstore:
y + z + x > 0

Now, we can solve for x to find the minimum number of comic books that Adriana must sell to meet her goal.

Since there are multiple values that satisfy this inequality, we'll assume values for y and z. Let's assume y = 1 and z = 1, to consider the minimum case for hardcover and paperback books.
18(1) + 8(1) + 6.50x ≥ 50
18 + 8 + 6.50x ≥ 50
26 + 6.50x ≥ 50
6.50x ≥ 24
x ≥ 24/6.50
x ≥ 3.692

Since x represents the number of comic books, we round it up to the nearest whole number because we cannot sell a fraction of a comic book. Therefore, Adriana must sell at least 4 comic books to earn no less than $50.