Question 831453
This is the same general form as another one, and can be solved the same way.  Any of these should help:


http://www.algebra.com/algebra/homework/word/travel/Travel_Word_Problems.faq.question.830443.html


http://www.algebra.com/algebra/homework/word/travel/Travel_Word_Problems.faq.question.831241.html


http://www.algebra.com/algebra/homework/word/travel/Travel_Word_Problems.faq.question.831367.html