A concert organizer learned from a market survey that when the admission price is $30, there is an average attendance of 800 people. For every $1 drop in price, there is a gain of 20 customers. Each customer spends an average of $5 on concessions. The concert hall has 1,000 seats.

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

According to point line form :

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

Thus, price in dollars for each ticket P = D(x) is:

c

step-by-step explanation:

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