Answer:
$7.54
Explanation:
Using the two-point form of the equation of a line, we can write the equation for the number tickets (t) as a function of price (p).
t = (t2 -t1)/(p2 -p1)(p -p1) +t1
t = (930 -1160)/(7 -5)(p -5) +1160
t = -230/2(p -5) +1160
t = -115p +1735 = -115(p -15 2/23)
The revenue from ticket sales will be the product of the price and the number of tickets sold:
r = pt = p(-115)(p -15 2/23)
This is the equation of a downward-opening parabola with zeros at p=0 and p=15 2/23. The vertex of the parabola (maximum revenue) will be found at a ticket price halfway between these values. The price for maximum revenue is ...
(0 +15 2/23)/2 = 7 25/46 ≈ 7.54
Rosalie should charge $7.54 per ticket to obtain the most revenue.