Answer:
The average revenue per passenger = E(x) = $15.70
[tex]\sigma = \sqrt{\sigma^{2}} = \sqrt{398} \approx 19.95[/tex]
b)$1,884 ± $20
Step-by-step explanation:
a)
Refer  attached fig for probability model,
i)The average revenue per passenger = E(x) = $15.70
[tex]\sigma^{2} = V[X] \sum _{x} (x-\mu )^{2} \times P(X=x)[/tex]
[tex]\sigma^{2} = (0-15.7)^{2} \times 0.54+(25-15.7)^{2} \times 0.34 +(60-15.7)^{2} \times 0.12[/tex]
[tex]\sigma^{2} = 133.1 + 29.4 + 235.5 = 398[/tex]
Standard Deviation = [tex]\sigma = \sqrt{\sigma^{2}} = \sqrt{398} \approx 19.95[/tex]
ii) Â average revenue per passenger = E(x) = $15.70
b) Revenue should the airline expect for a flight of 120 passengers
revenue = 120 * $15.70 = $1,884 ± $20 (or 19.95 rounded up)
use same σ