Answer:
[tex]\mathbf{ P =D(x)= 70 -\dfrac{ x}{20}}[/tex]
Step-by-step explanation:
From the information given :
The objective is to find the demand function which is expressed in p, the price in dollars charged for each ticket, as a function of x, and the number of average attendance is:
Suppose the admission price P = D(x) = 30 and number of average attendant = x = 800 people
Then:
ΔP = -1
Δx = 20
[tex]\left \{ \dfrac{\Delta x}{\Delta P }= -20 }}\ \right.[/tex]
According to point line form :
[tex]\dfrac{\Delta x}{\Delta P }= -20[/tex] where the point is (30, 800)
∴
x - 800 = -20 (P - 30)
x - 800 = -20P + 600
collect like terms
x + 20P = 800+ 600
x + 20P = 1400
x = 1400 - 20P
[tex]\mathsf{ P = 70 -\dfrac{ 1}{20}x}[/tex]
Thus, price in dollars for each ticket P = D(x) is:
[tex]\mathbf{ P =D(x)= 70 -\dfrac{ x}{20}}[/tex]