Question 609976
n(x) = -0.5x^2+13x+11
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Max occurs when x = -b/(2a) = -13/(2*-0.5) = 13/1 = 13
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Maximum number of tickets = n(13) = -(1/2)13^2+13*13 + 11 
= (-1/2)*169 + 169 + 11
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= 96 when rounded up to the nearest whole number
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Maximum sales occurs on day 13. 
# of tickets sold that day is 96 if rounded up
# of tickets sold that day is 95 if rounded down
Cheers,
Stan H.
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