Question 675773
Income disregards money that is going out. It's only about 
money coming in.
{{{ s = 4000-250x }}}
{{{ s }}} is NUMBER os tickets sold as a function of the
price of a single ticket.
The quantity {{{ s*x }}} is INCOME from total ticket sales
{{{ s*x = (4000-250x)*x }}}
{{{ I = 4000x - 250x^2 }}}
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Profit = income minus costs
{{{ P = I - ( 1000 + 3000 + 1500 + 2000 ) }}}
{{{ P = I - 7500 }}}
{{{ P = 4000x - 250x^2 - 7500 }}}
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Don't get desperate. Just think over the
basics of price, quantity produced, income, and profit
It takes practice.