Here are several computation practice exercises to help you identify which formulas pertain and learn how to perform the necessary calculations. In each case, perform the necessary calculations and write your answers in the column identified by a question mark.
a. Determine confidence intervals for each of the following:
1. Mean of 150, s.d. of 30, n of 200, level of 95% - Use mean equation
2. Percent of 67%, n of 300, level of 99% - Use percentage formula
3. Mean of 5.4, s.d. of 0.5, n of 250, level of 99% - Use mean formula
4. Percent of 25.8%, n of 500, level of 99% - Use percentage formula
b. Test the hypothesis and interpret your findings.
1. Hypothesis: mean=7.5, mean of 8.5, s.d. of 1.2, n of 670, level of 95%
2. Hypothesis: percent=86%, p of 95%, n of 1,000, level of 99%
3. Hypothesis: mean greater than 125, mean of 135, sd of 15, n of 500, level of 95%
4. Hypothesis: percent less than 33%, p of 31, n of 120, level of 99%