18. The average teacher’s salary in New Jersey is $50,174. Suppose that the distribution isnormal with...

18. The average teacher’s salary in New Jersey is $50,174. Suppose that the distribution isnormal with standard deviation equal to $4500. What is the probability that a randomly selected teacher makes less than $51,000?

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19. If we sample 100 teachers’ salaries, what is the probability that the sample mean is less than $51,000? (Use the information in #18 to assist you.)

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20. If we sample 500 teachers’ salaries, what is the probability that the sample mean is between $50,700 and $50,900? (Use the information in #18 to assist you.)

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orchestra answered 1 year ago

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