F(x) means "function of" and x represents the day number, example: day 6 would be f(6)=(20×6)+95
A. The mean and standard deviation.
The mean of a sampling distribution is approximately equal to the mean of the population. Given that the mean of the population is equal to 174.5, the mean of the sampling distribution is also this value.
The standard deviation of a sample distribution is equal to,
u(m) = u/sqrt n
Substituting the known values,
u(m) = 6.9 / sqrt 25 = 1.38
b. Get the z-score of both items,
z-score = (data point - mean) / standard deviation
z-score of 172.5
z-score = (172.5 - 174.5) / 1.38 = -1.49
This translates to 0.068.
z-score of 175.8
z-score = (175.8 - 174.5) / 1.38 = 0.94
This translates to 0.83.
The difference between the two z-scores is 0.762.
The number of samples with this height is 0.762(200) which is equal to approximately 152.
c. z-score of 172 centimeters
z-score = (172 - 174.5) / 1.38
z-score = -1.81
This translates to 0.03.
The number of people with this height from the sample is (0.03)(200) = 6
Answer:
Step-by-step explanation:
x, height of men is N(69, 2.8)
Sample size n =150
Hence sample std dev = 
Hence Z score = 
A) Prob that a random man from 150 can fit without bending
= P(X<78) = P(Z<3.214)=1.0000
B) n =75
Sample std dev = 
P(X bar <72) = P(Z<9.28) = 1.00
C) Prob of B is more relevent because average male passengers would be more relevant than a single person
(D) The probability from part (b) is more relevant because it shows the proportion of flights where the mean height of the male passengers will be less than the door height.
