A survey found that​ women's heights are normally distributed with mean 63.9 in. and standard deviation 3.6 in. The survey also found that​ men's heights are normally distributed with mean 69.7 in. and standard deviation 3.6 in. Consider an executive jet that seats six with a doorway height of 55.9 in. Complete parts​ (a) through​ (c) below. a. What percentage of adult men can fit through the door without​ bending? The percentage of men who can fit without bending is 0.02​%. ​(Round to two decimal places as​ needed.) b. Does the door design with a height of 55.9 in. appear to be​ adequate? Why​ didn't the engineers design a larger​ door?

Respuesta :

Answer:

a: 0.1%

b. No it does not

c.  Probably for safety reasons

Step-by-step explanation:

for women: z = (55.9 - 63.9)/3.6 = -2.22

The p-value for z = -2.22 is 0.0132, so only 1.32% of women could walk through without bending

for men: z = (55.9 - 69.7)/3.6 = -3.83

The p-value for z = -3.83 is 0.001, so only 0.1% of men could walk through without bending

Using the normal distribution, it is found that:

a) The percentage of men who can fit without bending is 0.02​%.

b) A very small percentage of people can fit through the door, thus the dimensions are not adequate. Possible, the engineers did not design a large door because of engineering constraints.

In a normal distribution with mean [tex]\mu[/tex] and standard deviation [tex]\sigma[/tex], the z-score of a measure X is given by:

[tex]Z = \frac{X - \mu}{\sigma}[/tex]

  • It measures how many standard deviations the measure is from the mean.  
  • After finding the Z-score, we look at the z-score table and find the p-value associated with this z-score, which is the percentile of X.

Item a:

  • Men have mean of 69.7 in, thus [tex]\mu = 69.7[/tex]
  • Standard deviation of 3.6 in, thus [tex]\sigma = 3.6[/tex]

The proportion is the p-value of Z when X = 55.9, thus:

[tex]Z = \frac{X - \mu}{\sigma}[/tex]

[tex]Z = \frac{55.9 - 69.7}{3.6}[/tex]

[tex]Z = -3.83[/tex]

[tex]Z = -3.8[/tex] has a p-value of 0.0002.

0.0002 x 100% = 0.02%

The percentage of men who can fit without bending is 0.02​%.

Item b:

A very small percentage of people can fit through the door, thus the dimensions are not adequate. Possible, the engineers did not design a large door because of engineering constraints.

A similar problem is given at https://brainly.com/question/12476124

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