Flight is $295 and car rental is $39 a day, if a competition charges $320 and $33 a day car rental,

Flight is $295 and car rental is $39 a day, if a competition charges $320 and $33 a day car rental, which is cheaper?

Set up cost function where d is the number of days:

• Control business: C(d) = 39d + 295
• Competitor business: C(d) = 33d + 320

Set the cost functions equal to each other:
We get d = 4.1667.

The next integer day up is 5. Now plug in d = 1, 2, 3, 4. For the first 4 days, the control business is cheaper. However, starting at day 5, the competitor business is now cheaper forever.