View Full Version : Find mean, variance and standard deviation, 45% out of 180.

05-15-2006, 04:33 PM
I am wondering if you can get me started on this question.

If 45% of nursing students are able to pass a drug calculation test, find the mean, variance, and standard deviation of the number of students who pass the test in a sample of 180 nursing students.

I know how to find mean when I have a list of numbers but I am not sure what to do with just one.

I am thinking that with the .45 I will use .55 somehow but again not sure.

Just so you know I am a 45 year old who decided to go back to school and statistics is not being kind to me.

05-15-2006, 05:52 PM
To get you started, the number of students who pass the test has a binomial distribution with parameters n = 180 and p = .45. The formulas for the mean, variance and standard deviation of this distribution should be in your textbook.

I wish you well with your return to school! :)