# stats -confidence intervals

**Question description**

A county is considering raising the speed limit on a road because they claim that the mean speed of vehicles is greater than 45 miles per hour. A random sample of 25 vehicles has a mean speed of 48 miles per hour and a standard deviation of 5.4 mph. Find the 95% confidence interval for the speed limit.

Find the critical value

- Find the margin of error: E
- Find the confidence interval: CI =
- Write the conclusion.

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