SOLUTION: A soccer stadium holds 31,000 spectators. With a ticket price of $11, the average attendance has been 13,000. Market research has shown that for every $2 reduction in price, attend

Algebra ->  Probability-and-statistics -> SOLUTION: A soccer stadium holds 31,000 spectators. With a ticket price of $11, the average attendance has been 13,000. Market research has shown that for every $2 reduction in price, attend      Log On


   



Question 999839: A soccer stadium holds 31,000 spectators. With a ticket price of $11, the average attendance has been 13,000. Market research has shown that for every $2 reduction in price, attendance will rise by 2,500. Assuming that attendance is linearly related to ticket price, what ticket price would maximize revenue?
Answer by Theo(13342) About Me  (Show Source):
You can put this solution on YOUR website!
first you want to create the formula for attendance.

this will be a straight line equation.

when x = 11, attendance is 13000
when x = 9, attendance is 15500

these are two coordinate points on your graph.

(x1,y1) is the first point.
(x2,y2) is the second point.

you have:

(x1,y1) = (11,13000)
(x2,y2) = (9,15500)

the slope intercept form of the equation for a straight line is y = mx + b.

m is the slope
b is the y-intercept.

given two points, m = (y2-y1) / (x2-x1).

this becomes (15500 - 13000) / (9 - 11) = 2500 / -2 = -1250

your slope is -1250.

y = mx + b becomes y = -1250x + b

to find b, take any coordinate point on the line and replace y with the y-coordinate and replace x with the x-coordinate and solve for b.

we'll use (x1,y1) = (11,13000)

y = -1250x + b becomes 13000 = -1250*11 + b

solve for b to get b = 13000 + 1250*11 = 26750

y = -1250x + b becomes y = -1250x + 26750.

that is the equation for attendance.

the graph of that equation is shown below:

$$$

based on the formula, you can see on the graph that:

when x = 0, attendance is 26750.
when x = 21.4, attendance is 0.
when x = 11, attendance is 13000.

not shown on the graph, but calculated from the formula, you also get:

when x = 9, attendance is 15000, confirming that the equation is good.

revenue is equal to attendance times price.

let y = revenue
let x = price
let -1250x + 26750 = attendance

equation becomes:

y = (-1250x + 26750) * x

you can graph this equation as is, or you can simplify it to get:

y = -1250x^2 + 26750x

you will get the same graph either way.

you can find the maximum value of y from the graph, or you can derive it from the quadratic equation formula of x = -b/2a and y = f(-b/2a)

in the equation of y = -1250x^2 + 26750x:

a = -1250
b = 26750

x = -b/2a = -26750 / -2500 = 10.7

f(-b/2a) becomes f(10.7)

replace x in the equation with 10.7 and you get:

y = -1250*10.7^2 + 26750*10.7 = 143112.5 which is shown as 143113 on the graph.

that is the maximum revenue that can be attained based on the formula.

the graph of the revenue equation is shown below:

$$$