Problem 05 Empirical Rule : Several years of final exam scores in statistics courses for a...

Problem 05 Empirical Rule : Several years of final exam scores in statistics courses for a local university are normally distributed with a mean of 81 and a standard deviation of 8. If the lowest 2.5% of the scores on this test qualifies for a failing grade (F), use the empirical rule to calculate the score a student would need on this test to pass the final exam? show your work integer answer

Problem 08 Expected Value and Life Insurance Payouts : There is a 0.9985 probability that a randomly selected 60-year-old female lives through the year U.S. Department of Health and Human Services. A Fidelity life insurance company charges $180 for insuring that the female will live through the year. If the female does not survive the year, the policy pays out $100,000 as a death benefit.

From the perspective of the 60-year-old female, what are the monetary values corresponding to the two events of surviving the year and not surviving?

If a 60-year-old female purchases the policy, what is her expected value?

Can the insurance company expect to make a profit from many such policies? Why?

Problem 11 Continuous Random Variables: Empirical Rule: Scores on an examination are assumed to be normally distributed with mean 78 and variance 10. Suppose that students scoring in the top 10% of this distribution are to receive an A grade. If you are asked “What is the minimum score a student must achieve to earn an A grade?”, can you use the empirical rule to answer this question? Explain your answer.

Expert Solution

orchestra answered 2 years ago

for a final exam in statistics , the mean of the exam scores is u= 75...

for a final exam in statistics , the mean of the exam scores is u= 75 with a standard deviation of o=8. what sample mean marks the top 10% of this distribution for a samples of n= 25 b) what sample means mark the boundaries of the middle 50% for samples of n= 50

Below are the final exam scores of 20 Introductory Statistics students.

Below are the final exam scores of 20 Introductory Statistics students. Student 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 Score 71 76 77 77 79 80 80 80 81 81 84 84 85 86 86 86 86 87 89 93 The mean exam score is 82.4 with a standard deviation of 5.14. 1. How many of the exam scores in the sample are within one standard deviation...

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A sample of 10 students record their scores on the final exam for their statistics class....

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An investigator collected data on midterm exam scores and final exam scores of elementary school students;...

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A) Suppose that the mean and standard deviation of the scores on a statistics exam are...

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