SOLUTION: Suppose 40% of a student population works part time. If a random sample size of 300 students is drawn from the population, then the probability that 44% or fewer of the samples wor

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Question 1137277: Suppose 40% of a student population works part time. If a random sample size of 300 students is drawn from the population, then the probability that 44% or fewer of the samples work part time is:
Answer by rothauserc(4718) About Me  (Show Source):
You can put this solution on YOUR website!
standard deviation of the sample proportion = square root(0.40 * (1-0.40) / 300) = 0.0283
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The population proportion is 0.40
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since the sample size is > 30, we can use the Normal distribution
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z-score = (0.44 - 0.40) / 0.0283 = 1.4134 is approximately 1.41
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look in z-table to find the probability corresponding to a z-score of 1.41
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Probability ( X < 0.44 ) = 0.9207 is approximately 0.92
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