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Hypothesis Testing of Mean

1. The U.S. Fish and Wildlife Service's report on the bass population in the North American lakes indicated average weight of the fish to be 3.0 lb. and a standard deviation of .30 lb. Furthermore, 50% of all bass were females. The State of Florida conducted an independent study and reported the average weight of their bass was 3.2 lb, but did not disclose the standard deviation. Additionally, the report indicated that 58% of bass's population were found to be females.
(This report was based on a small sample of 121 fish)

Test the hypothesis that Florida's bass weighs more than average bass in the U.S.A. Use alpha = .1 to state your conclusion.

H0: Xavg = mu
H1: Xavg > mu

Please note that "alpha" and "mu" represent respective Greek symbols.

2. A study of recent graduates revealed that for a sample of ten accounting majors the mean salary was $30,000 per year with a sample standard deviation of $2,000. A sample of eight general business majors revealed a mean salary of $29,000 per year with a standard deviation of $1,500. At the .05 significance level can we conclude accounting majors earn more?

3. The dean of college of business wants to determine if the GPA decreases during the last semester of senior year. A sample of 6 students is selected. Their GPAs for the fall and spring semesters of their senior year are:

Student Fall sem. GPA Spring sem. GPA
A 2.7 3.1
B 3.4 3.3
C 3.5 3.3
D 3.0 2.9
E 2.1 1.8
F 2.7 2.4

Using .05 significance level, can the Dean conclude that the GPA of graduating students declined during their last semester?

Solution Summary

The solution provides step by step method for the calculation of testing of hypothesis. Formula for the calculation and Interpretations of the results are also included. Interactive excel sheet is included. The user can edit the inputs and obtain the complete results for a new set of data.