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Re: Max. Income, Quadratic Equation
Posted:
Feb 15, 2005 4:48 PM


On Tue, 15 Feb 2005 04:49:05 GMT, "Darrell" <dr6583@comcastsnip.net> wrote:
>>> A plane with 100 seats may be chartered for $200 per person plus a fee >>> of $5 per person for each empty seat. What number of passengers will >>> provide the maximum income?
>> Let p be the number of passengers and i the income then >> >> i = p*200 + p*(100  p)*5 >> = 700*p  5p^2 >> >> and you need to maximize i. Note that it makes no sense to >> differentiate i wrt p because neither is a continuous variable. > >That doesn't matter; for all intents and purposes the problem can be >modelled by this (continuous) function.
Agreed. Any problem in misunderstanding can be avoided if algebra [completing the square] is used instead in this instance.
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