We have a smuggled total that is 15.#4 after buying 18 bottles.
We can estimate the cost of each bottle as:
where x is the tenths of a dollar, and it will have an integer value between 0 and 9.
If we try the different possible values for x, we get:
We can see that the only value that give a unit price in cents is for x = 8, which corresponds to a total price of $15.84 and a unit price of $0.88.
Answer: we can estimate that the unit price is $0.88.