Given : Based on FAA estimates the average age of the fleets of the 10 largest U.S. commercial passenger carriers is $\mu=13.4$ years and standard deviation is $\sigma=1.7$ years.

Sample size : $n=40$

Let X be the random variable that represents the age of fleets.

We assume that the ages of the fleets of the 10 largest U.S. commercial passenger carriers are normally distributed.

For z-score,

$z=\dfrac{x-\mu}{\dfrac{\sigma}{\sqrt{n}}}$

For x=14

$z=\dfrac{14-13.4}{\dfrac{1.7}{\sqrt{40}}}\approx2.23$

By using the standard normal distribution table , the probability that the average age of these 40 airplanes is at least 14 years old will be :-

$P(x\geq 14)=P(z\geq2.23)\\\\=1-P(z$

Hence, the required probability = 0.0129

6 0

3 years ago

What is the greatest possible error of the measurement?

dezoksy [38]

I think it would be A. 9.6. I'm completely sure on that one.

4 0

3 years ago

Read 2 more answers

What power of 10 exceeds 972

nika2105 [10]

10 to the power of 3, because it equals 1,000, which exceeds 972. I'm in elementary school, so I am not too sure if this is what you are asking. Hope it helps.

7 0

3 years ago

A set of n = 15 pairs of X and Y scores has SSX = 10, SSY = 40, and SP = 30. What is the slope for the regression equation for p

Mumz [18]

Answer:

Step-by-step explanation:

We have given $SS_X=10$ , $SS_Y=40$ and SP =30