To solve this problem, we need to determine the value of x, which represents the number of miles Ann would need to travel in order to be charged $168.
We know that Ann was charged $120 for traveling 50 miles.
We can set up the proportion as follows:
$120 / 50 miles = $168 / x miles
To solve for x, we can cross multiply:
$120 * x miles = $168 * 50 miles
$120x = $8400
To isolate x, we divide both sides of the equation by $120:
$120x / $120 = $8400 / $120
x = 70
The value of x is 70.
The answer is: 70
Below is a math problem. Provide a detailed, step-by-step solution.

### Problem:
After traveling 50 miles by taxi, Ann is charged a fare of $\$120$. Assuming the taxi fare is directly proportional to distance traveled, Ann would be charged 168 dollars if she had traveled X miles. What is the value of unknown variable X?

### Answer:
