The housing market has recovered slowly from the economic crisis of 2008. Recently, in one large community, realtors randomly sampled 45 bids from potential buyers to estimate the average loss in home value. The sample showed the average loss was $10,560 with a standard deviation of $1800. a) Find a 95% confidence interval for the mean loss in value per home. (Use your calculator to create this interval. Do not do the calculations by hand.) b) Interpret this interval. c) A neighborhood realtor predicted the average loss in value would be $11,000. Based on your interval in part b, is the realtor right or wrong?

Part b ?

You are a researcher studying a certain species of fish in a local lake.  You gather a random sample of 19 fish of this species and record the lengths (in centimeters) of the fish. The data is displayed in the table below.  Estimate the mean length of all fish of this type in the lake.  Use a 99% confidence level. 9.1 9 8.6 5.8 9.8 7.4 9.1 9.5 8.2 8.9 9.3 7.8 9 9.6 10.4 13.6 7.2 10.1 8.9   a)  Find the confidence interval:  b) What is the margin of error of your interval?  c) Interpret your 99% confidence interval in context

Two friends, Karen and Jodi, work different shifts for the same ambulance service. They wonder if the different shifts average different numbers of calls. Looking at past records, Karen determines from a random sample of 32 shifts that she had a mean of 4.8 calls per shift. She knows that the population standard deviation for her shift is 1.4 calls. Jodi calculates from a random sample of 40 shifts that her mean was 4.2 calls per shift. She knows that the population standard deviation for her shift is 1.1 calls. Test the claim that there is a difference between the mean numbers of calls for the two shifts at the 0.01 level of significance. Let Karen's shifts be Population 1 and let Jodi's shifts be Population 2.   Step 2 of 3 :   Compute the value of the test statistic. Round your answer to two decimal places.