SOLUTION: Given a normal distribution with µ = 100 and σ = 10, if you select a sample of n = 25, what is the probability that x¯ is:
a. less than 47?
b. between 95 and 97.5?
c. above
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-> SOLUTION: Given a normal distribution with µ = 100 and σ = 10, if you select a sample of n = 25, what is the probability that x¯ is:
a. less than 47?
b. between 95 and 97.5?
c. above
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Question 685934: Given a normal distribution with µ = 100 and σ = 10, if you select a sample of n = 25, what is the probability that x¯ is:
a. less than 47?
b. between 95 and 97.5?
c. above 102.2?
d. there is a 65% chance that x¯ is above what value? Answer by stanbon(75887) (Show Source):
You can put this solution on YOUR website! Given a normal distribution with µ = 100 and σ = 10, if you select a sample of n = 25, what is the probability that x-bar is:
a. less than 47?
z(47) = (47-100)/[10/sqrt(25)] = -52/2 = -26
P(x-bar < 47) = P(z < -26) is very close to zero.
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b. between 95 and 97.5?
Find the z-value corresponding to 95 and 97.57
Find the Probability between those z values.
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c. above 102.2?
Find the z-value of 102.2
Find the probability that z is above that z-value.
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d. there is a 65% chance that x-bar is above what value?
Find the z-value with a left tail of 0.35
invNorm(0.35) = -0.3853
Find the x-bar value using x-bar = z*s + u
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x-bar = -0.3853*2+100 = 99.23
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Cheers,
Stan H.
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