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Calculating the test statistic in a t test for a mean

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St. West High School requires that students are assigned an average of 2.5 hours of homework each night. The school board believes that the average amount of time per night is not 2.5 hours, so they decide to take a random sample of 16 students to see if there is convincing evidence to support their suspicion. The board finds that the sample of students were assigned an average of 2.8 hours of homework per night with a standard deviation of 0.8 hours.
The board want to use these sample data to conduct a t test on the mean. Assume that all conditions for inference have been met.
Calculate the test statistic for their test.
You may round your answer to two decimal places.
  • Your answer should be
  • an integer, like 6
  • a simplified proper fraction, like 3/5
  • a simplified improper fraction, like 7/4
  • a mixed number, like 1 3/4
  • an exact decimal, like 0.75
  • a multiple of pi, like 12 pi or 2/3 pi