A leading magazine (like Barron's) reported at one time that the average number of weeks an individual is unemployed is 12 weeks. Assume that for the population of all unemployed individuals the population mean length of unemployment is 12 weeks and that the population standard deviation is 6.9 weeks. Suppose you would like to select a random sample of 170 unemployed individuals for a follow-up study.

Find the probability that a single randomly selected value is between 10.7 and 11.8.

P(10.7

Find the probability that a sample of sizen=170n=170is randomly selected with a mean between 10.7 and 11.8.

P(10.7

In a study about undergraduate student credit card usage, it was reported that undergraduate students have a mean credit card balance of $3173 (Sallie Mae, April 2009). This figure was an all-time high and had increased 44% over the previous five years. Assume that a current study is being conducted to determine if it can be concluded that the mean credit card balance for undergraduate students has continued to increase compared to the April 2009 report. Based on previous studies, assume a population standard deviation of 1700. Suppose you look at a random sample of 165 undergraduate students with a sample mean credit card balance of $3239.2. You wish to test the claim that the mean credit card balance is higher than it was in 2009 at the==0.02 level. What is the test statistic for this sample? test statistic =( )(Report answer accurate to 3 decimal places.) What is the p-value for this sample? p-value =( )(Report answer accurate to 4 decimal places.) The p-value is...

• aless than (or equal to)
• b..greater than

This test statistic leads to a decision to...

• A.reject the nullBaccept the null
• C.fail to reject the null

As such, the final conclusion is that...

• A.There is sufficient evidence to warrant rejection of the claim that the population mean is greater than 3173.
• B.There is not sufficient evidence to warrant rejection of the claim that the population mean is greater than 3173.
• C.The sample data support the claim that the population mean is greater than 3173.
• D,Thereisnotsufficientsampleevidencetosupporttheclaimthatthepopulationmeanisgreaterthan3173.

Use ONLY the Standard Normal Tables (Link) to answer the following... A set of exam scores is normally distributed and has a mean of 71.2 and a standard deviation of 7.5. What is the probability that a randomly selected score will be greater than 64?

Answer =( )(round to four decimal places)