Question 361195: Assume that the average annual salary for a worker in the United States is $37,500 and that the annual salaries for Americans are normally distributed with a standard deviation equal to $7,000. Find the following:
(A) What percentage of Americans earn below $27,000?
(B) What percentage of Americans earn above $45,000?
Please show all of your work.
Answer by stanbon(75887)   (Show Source):
You can put this solution on YOUR website! Assume that the average annual salary for a worker in the United States is $37,500 and that the annual salaries for Americans are normally distributed with a standard deviation equal to $7,000. Find the following:
(A) What percentage of Americans earn below $27,000?
Find the z-value of 27000.
z(27000) = (27000-37500)/7000 = -1.5
Find the probability that z could be lower.
P(x < 27000) = P(z< -1.5) = 0.0668
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I get 0.0668
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(B) What percentage of Americans earn above $45,000?
Find the z-value of 45000.
z(45000) = (45000-37500)/7000 = 1.0714..
Find the probability that z could be higher.
P(x > 45000) = P(z > 1.0714) = 0.1420
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I get 0.1420
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Cheers,
Stan H.
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