# Worksheet: Confidence Intervals for Population Means

In this worksheet, we will practice calculating 90%, 95%, and 99% confidence intervals for the population means.

**Q3: **

The number of hours students spend on homework each week is known to be distributed with a standard deviation of 3.21 hours. A sample of 50 students were asked how many hours they spend doing homework in a week and the results are given in the table.

Hours | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 |
---|---|---|---|---|---|---|---|---|---|

Number of Students | 4 | 5 | 8 | 10 | 4 | 7 | 9 | 2 | 1 |

Find the sample mean.

Calculate a confidence interval for the population mean.

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