## Need help w/ word prob: rental agency charges \$40/day plus

Limits, differentiation, related rates, integration, trig integrals, etc.
cpoolrn
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### Need help w/ word prob: rental agency charges \$40/day plus

A certain car rental agency charges \$40 per day with 100 free miles plus 0.34 cents per mile after the first 100 miles. First express the cost of renting a car from this agency for one day in terms of the number of miles driven. Then draw the graph and use it to check your answers to these questions.

a. How much does it cost to rent a car for a 1-day trip of 50 mi?

b. How many miles were driven if the daily rental cost was \$92.36?

Thanks in advance. I appreciate any help I can get.

stellar
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Joined: Wed Mar 25, 2009 7:40 pm

### Re: Need help with word problem?

i'm not sure how this is calculus?? you can do this with algebra. the 1st 100 mi are free, so its C(x) = 40 + 0.34*(x-100) if x is the distance, assuming you did more than 100 mi. Its just \$40 for 100 and under.

if you've done piecewise stuff, that would probably work here. then for a, just use the number they gave you for the 1st 100, and for b, plug the cost in and solve for x.

cpoolrn
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### Re: Need help w/ word prob: rental agency charges \$40/day pl

Thank you! This problem came from my Calc I book, but they are reviewing Algebra.