1. Not finding help here? Sign up for a free 30min tutor trial with Chegg Tutors
    Dismiss Notice
Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

Rational Function Question

  1. Dec 15, 2007 #1
    1. The problem statement, all variables and given/known data
    Queuing Theory (study of lines for stores) says that for a drive through window at a Macdonalds, the function

    f(x)= 9/(x(x-9))

    represents the average time in hours a customer will wait in line. X=average number of people an hour.
    How long will a customer have to wait in line (on average)?

    3. The attempt at a solution

    Not sure at all on how to find an average time out of this function.
  2. jcsd
  3. Dec 15, 2007 #2


    User Avatar
    Staff Emeritus
    Science Advisor
    Gold Member

    Were you given a value for x?
  4. Dec 15, 2007 #3
    The question I think says 9<x<or=20
  5. Dec 15, 2007 #4


    User Avatar
    Staff Emeritus
    Science Advisor

    Yes, x will have to be larger than 9 for that function to be positive- and I've never had a negative waiting time at McDonald's! The average of a function, f(x), over [itex]a\le x\le b[/itex] is
    [tex]\frac{\int_a^b f(x)dx}{b-a}[/tex]
Know someone interested in this topic? Share this thread via Reddit, Google+, Twitter, or Facebook

Have something to add?

Similar Discussions: Rational Function Question