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Homework Help: Neighborhoods of functions (problem)

  1. Apr 3, 2006 #1
    I need help on neighborhoods of functions:

    38. The owner of a pizza parlor says money is lost on a medium size pizza, which has a 14-inch diameter, if its area exceeds 176 square inches. Customers complain if the area is less than 132 square inches. What tolerance is allowed for the diameter? use 22/7 as an approximation for pi.

    This is what I've got:
    [tex]176<(22/7 \times 7^2)< 132[/tex]

    What exactly does it mean by tolerance and I know that I'm missing a variable but I'm not sure where the variable goes.
  2. jcsd
  3. Apr 3, 2006 #2
    you don't want the area to be more than 176 square inches because you'll lose money and you don't want it to be less than 132 because the customers will complain

    132<=22/7 * 7^2 <= 176

    I think by tolerence they mean how much can the diameter vary or change from 7 inches so that the area of the pizza is still within these limits
  4. Apr 4, 2006 #3
    ahhh I see now
    [tex]132<22/7 \times r^2<176[/tex]

    so just solve for r I think.
    thanks buzz that made more sense.
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