Question

In order to estimate the mean amount of time computer users spend on the internet each​ month, how many computer users must be surveyed in order to be 95​% confident that your sample mean is in error by no more than 14 ​minutes? Assume that the standard deviation of the population of monthly time spent on the internet is 190 min. Use technology to find the estimated minimum required sample size.
The minimum sample size required is __ computer users.
​(Round up to the nearest whole​ number.)

Use the given information to find the number of degrees of​ freedom, the critical values chi Subscript Upper L Superscript 2 and chi Subscript Upper R Superscript 2​, and the confidence interval estimate of sigma. It is reasonable to assume that a simple random sample has been selected from a population with a normal distribution.
Platelet Counts of Women 95​% ​confidence; n=26​, s=65.7

df=__ ​(Type a whole​ number.)

chi Subscript Upper L Superscript 2=__
​(Round to three decimal places as​ needed.)

chi Subscript Upper R Superscript 2=__
​(Round to three decimal places as​ needed.)

The confidence interval estimate of sigma is __ less than sigma less than __
​(Round to one decimal place as​ needed.)

Answer 1