A study was made to estimate the difference in salaries of college professors in the private and state colleges of Virginia. A random sample of 100 professors in private colleges showed an average 9-month salary of $26,000 with a standard deviation of $1300. A random sample of 200 professors in state colleges showed an average salary of $26,900 with a standard deviation of $1400. Test the hy- pothesis that the average salary for professors teaching in state colleges does not exceed, the average salary for professors teaching in private colleges by more than $500. Use a 0.02 level of significance.

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