SOLUTION: 5. The air pressure in a randomly selected tire put on a certain model new car is normally distributed with a mean value 31 psi and standard deviation 1 psi.
a) What is the
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-> SOLUTION: 5. The air pressure in a randomly selected tire put on a certain model new car is normally distributed with a mean value 31 psi and standard deviation 1 psi.
a) What is the
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Question 914487: 5. The air pressure in a randomly selected tire put on a certain model new car is normally distributed with a mean value 31 psi and standard deviation 1 psi.
a) What is the probability that the pressure for a randomly selected tire is between 30 psi and 32 psi?
b) What is the maximum tire pressure for the bottom 25% of the cars?
c) What is the median tire pressure of all cars of this model?
d) If a sample of 25 tires is selected, what is the probability that the average air pressure of these tires is more than 31.5 psi?
You can put this solution on YOUR website! normally distributed with a mean value 31 psi and standard deviation 1 psi.
a) What is the probability that the pressure for a randomly selected tire is between 30 psi and 32 psi?
Empirical Rule(1SD from mean) 68%
one standard deviation from the mean accounts for about 68% of the set
two standard deviations from the mean account for about 95%
and three standard deviations from the mean account for about 99.7%.
0r P = normalcdf(30,32,31,1)
0r P = normalcdf(-1,1)
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b) What is the maximum tire pressure X for the bottom 25% of the cars?
1(invNorm(.25) + 31 = X
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c) What is the median tire pressure of all cars of this model?
Normal Distribution(Mean Median & Mode the same): 31 psi
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d) If a sample of 25 tires is selected, what is the probability that the average air pressure of these tires is more than 31.5 psi? = 2.5,
P(x > 31.5) = normalcdf(2.5,100)
