# statistics

posted by
**Ann** on
.

My mean is 175.5 My standard deviation is=90.57 Sample=25 Formula to be used: P(X>190)=P((X-mean)/s sqrt of my sample is = 5 (Which is the square root of 25.)(190-175.5) / 90.57/5) 14.5/18.114 calculator says 0.8004858120790548746825659710721 I check the z-table and I see -.8 under the z of 0.00 correlates to .2119

So the probability is =0.2119

Select a random sample of 30 student responses to question 6, "How many credit hours are you taking this term?" Using the information from this sample, and assuming that our data set is a random sample of all Kaplan statistics students, estimate the average number of credit hours that all Kaplan statistics students are taking this term using a 95% level of confidence. Be sure to show the data from your sample and the data to support your estimate.