|
Question 104274: Please help with this problem, I can't seem to get it set up right, Thanks in advance.
John and Sherry needed to rent a car for a week.Avis wanted $28 per day, with no mileage fee. Toyota wanted $108 per week and $.14 per mile. How many miles would they have to drive before the Avis price is less than the Toyota price?
Answer by mathnard(10)   (Show Source):
You can put this solution on YOUR website! Now this problem is easier than it looks. I can already guess where your mistakes are. REMEMBER: John and Sherry are renting for 1 week.
Let's start with AVIS. Since there are no mileage fees, this means that the price John and Sherry will pay will be equal to 7 days of the $28 fee.
7x28=196.
That's pretty expensive.
AVIS: $196 per week
TOYOTA: 108 plus .14 for every mile driven?
We can write an equation:
Cost = 108 + 0.14(m) where m is the number of miles driven
So the two companies will be the same price when?
When AVIS's cost is equal to TOYOTA's cost!
196 = 108 + 0.14(m)
-108 -108
88 = 0.14m
SO m = 88/0.14 or 628.57 miles.
Ok, great. What does that mean? It means that Toyota's cost keeps getting more expensive while AVIS is always at $198. It means that at 628 miles, Toyota is still cheaper. But at 629 miles, Avis has magically become the cheaper deal.
Now, let me guess your mistake: did you write your equation for Toyota without the decimal point? (108 + 14m) Don't forget that we don't mean 14 dollars every mile!!!! You meant to put .14 dollars per mile.
|
|
|
| |
