The cost to rent a movie is $37 plus an additional of $18 per hour
This implies that the flat rate to rent a movie is $37 and the charges per hour is $18
Let x be the number of hours
Setting up an algebraic equation
T = $37 + $18 * x
T = 37 + 18x
T is the total amount spend on the movie
The total amount spent is $91
Therefore,
91 = 37 + 18x
Let make 18x the subject of the formula
18x = 91 -37
18x = 54
Divide both sides by 54
18x/18 = 54 / 18
x = 3 hours
Since x represent the number of hours
Then, the maximum amount of time that a movie can be rented at $91 is 3 hours
The answer is 3 hours