Scores on an MBA placement exam are reported to have a normal distribution with standard deviation...

Scores on an MBA placement exam are reported to have a normal distribution with standard deviation 18. The exam officials stated that the average score for all students was 70. You take a random sample of 50 students and find their average score is 67. Use your data to estimate the mean score for all students taking the MBA placement exam -Verify your answer using calculations and show your work.

Students at the union want to estimate the average number of ounces of coffee in a cup. They take a random sample of 40 cups and find the mean is 5.2 ounces. Assume amount dispensed has a normal distribution and that the standard deviation is set at 0.24 ounces per cup. Find your best estimate for the average amount of coffee being dispensed by this machine. Verify your answer using calculations and show your work.

Solutions

Expert Solution

Answer 1)

Thus, at 0.05 significance level, there is not enough evidence to claim that the average score for all students is different than 70.

Answer 2)

We are 95% confidence that the average amount of coffee being dispensed by this machine is between 5.138 and 5.262 ounces.

milcah answered 3 months ago

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