AP Statistics › Confidence Intervals
An automotive engineer wants to estimate the cost of repairing a car that experiences a 25 MPH head-on collision. He crashes 24 cars, and the average repair is $11,000. The standard deviation of the 24-car sample is $2,500.
Provide a 98% confidence interval for the true mean cost of repair.
An automotive engineer wants to estimate the cost of repairing a car that experiences a 25 MPH head-on collision. He crashes 24 cars, and the average repair is $11,000. The standard deviation of the 24-car sample is $2,500.
Provide a 98% confidence interval for the true mean cost of repair.
An automotive engineer wants to estimate the cost of repairing a car that experiences a 25 MPH head-on collision. He crashes 24 cars, and the average repair is $11,000. The standard deviation of the 24-car sample is $2,500.
Provide a 98% confidence interval for the true mean cost of repair.
The population standard deviation is 7. Our sample size is 36.
What is the 95% margin of error for:
the population mean
the sample mean
The population standard deviation is 7. Our sample size is 36.
What is the 95% margin of error for:
the population mean
the sample mean
The population standard deviation is 7. Our sample size is 36.
What is the 95% margin of error for:
the population mean
the sample mean
The confidence interval created for the difference in means between two training programs for middle distance college runners is
. The variable being measured is the improvement in seconds of mile times over the course of a season. One program has more speed work and intervals, while the other focuses more on distance training.
What does the confidence interval tell us about the difference in the two programs?