what is the single sample t-test calculation when a A manager wishes to compare the overtime expenses he has accrued for his office over the last 12 weeks to the company average of $2200. Using a single-sample t-test, test the hypothesis that a need exists to reduce overtime expenses for his office. The following data represents his overtime expenses for a 12 week period: 2700, 2100, 1800, 2600, 2250, 3100, 1700, 2350, 2800, 2400, 2200, 1900