Answer:
80n+20=total cost
Explanation:
We don't know the value of n, but we don't need it for an expression. We know that the family has to pay $80 per night that they stay at the hotel. Modeling this would look like: 80n (80*n for nights). Also, we know that the family MUST pay a $20 fee. So, we can add that on to the expression to look like this, 80n+20=total cost.
Hope this helps!
Have a nice evening.