# Calculus

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A baseball team plays in a stadium that holds 53,000 spectators. With ticket prices at \$10, the average attendance had been 49,000. When ticket prices were lowered to \$8, the average attendance rose to 51,000.
(a) Find the demand function (price p as a function of attendance x), assuming it to be linear.
P(x)=_____

How should ticket prices be set to maximize revenue? (Round your answer to the nearest cent.)
\$_________________

• Calculus - ,

k is for thousands
(49 k, 10) and (51 k, 8)
slope = (8-10)/(51 k - 49 k) = -1/1k

p = -(1/k)x+ b
10 = -(1/k)49 k + b
59 = b
so
p = -(1/k)x + 59 or p = -x/1000 + 59

r = x p
r = -x^2/1000 + 59 x
x^2 -59000 x = 1000 r
x^2 - 59000 x + 29,500^2 = 1000 r + 29,500^2
(x-29,500)^2 = 1000(r + 870,250)
so max r at x = 29,500 people and revenue of 870,250
then price = 870,250/29,500 = \$29.50
then p =

• Calculus - ,

By the way there is no need to use calculus for these since you can complete the square to find the vertex of a parabola with algebra 2.

• Calculus - ,

Oh okay, thank you!

• Calculus - sign error (does not matter) - ,

r = x p
r = -x^2/1000 + 59 x
x^2 -59000 x = -1000 r
x^2 - 59000 x + 29,500^2 = -1000 r + 29,500^2
(x-29,500)^2 = 1000(r - 870,250)
so max r at x = 29,500 people and revenue of 870,250
then price = 870,250/29,500 = \$29.50

• Calculus - ,

i feel like you solved for when the stadium holds 59000 not 53000 like in his question hahaha WHICH IS PERFECT BECAUSE MY PROBLEM IS WITH 59000! yay :)