A city planner wants to estimate the mean commute time in minutes for residents. The population standard deviation is 1515 minutes. What is the minimum sample size needed to be 90%90\% confident that the sample mean is within 44 minutes of the true mean?

A city planner wants to estimate the mean commute time in minutes...

Confidence Intervals for Population Mean: Videos & Practice Problems

A city planner wants to estimate the mean commute time in minutes for residents. The population standard deviation is 1515 minutes. What is the minimum sample size needed to be 90%90\% confident that the sample mean is within 44 minutes of the true mean?

A city planner wants to estimate the mean commute time in minutes for residents. The population standard deviation is $15$ minutes. What is the minimum sample size needed to be $90 percent sign$ confident that the sample mean is within $4$ minutes of the true mean?