Maddie makes herself 2 cups of coffee per day, so she makes 2 * 7 = 14 cups of coffee per week.
Each cup of coffee has x ounces of coffee beans, so she uses 14 * x ounces of coffee beans per week.
A bag of coffee costs $8 and contains 10.5 ounces of beans, so the cost of the coffee beans Maddie uses per week is (14 * x) / 10.5 * $8.
She uses 1/2 a gallon of milk per week, which costs (1/2) * $4 = $2.
The total cost of Maddie's coffee per week is the cost of the coffee beans plus the cost of the milk: (14 * x) / 10.5 * $8 + $2.
We are given that the total cost per week is $18, so we can write: (14 * x) / 10.5 * $8 + $2 = $18.
Simplifying the left side, we get: (112 * x) / 10.5 + $2 = $18.
Subtracting $2 from both sides, we get: (112 * x) / 10.5 = $16.
Multiplying both sides by 10.5, we get: 112 * x = $16 * 10.5.
Dividing both sides by 112, we get: x = $16 * 10.5 / 112.
Calculating the right side, we get: x = $1.5.
The value of x is $1.5.
#### 1.5
The answer is: 1.5
Below is a math problem. Provide a detailed, step-by-step solution.

### Problem:
Maddie wants to see how much her mom spends on coffee each week. She makes herself 2 cups of coffee per day. Each cup has x ounces of coffee beans. A bag of coffee costs $8 and contains 10.5 ounces of beans. She uses 1/2 a gallon of milk per week. A gallon of milk costs $4. She doesn't add any sugar to the coffee. How much does she spend on her coffee per week?
If we know the answer to the above question is 18, what is the value of unknown variable x?

### Answer:
