We have two rental car plans.
We have to compare them to find the one that offers the minimum cost.
Plan A has no fixed fee but has a cost of $30 per day:
[tex]C=30d[/tex]
Plan B has a fixed fee of $15 and a cost per day of $25:
[tex]C=25d+15[/tex]
We expect the plan A to have a smaller cost for few days, while plan B becomes more convenient when we increase the number of days.
We can calculate the break even point when both costs are the same:
[tex]\begin{gathered} C_A=C_B \\ 30d=25d+15 \\ 30d-25d=15 \\ 5d=15 \\ d=\frac{15}{3} \\ d=5 \end{gathered}[/tex]
Then, we know that for less than 5 days, Plan A is more convenient.
For more than 5 days, Plan B is more convenient.
For exactly 5 days, the decision is indifferent as both plans will have the same total cost.
Answer: The only statement that would justify selecting Plan B instead of A is if Marcus rents a car for 5 days.
