Taking a statistics class with the luxury of being able to use excel. I found
most of the formulas I need but I am still stuck on a few that I could not
find from excel help. Anyone that could help with link to any sites with how
to enter these Statistic formulas into excel or could explaini them here it
would greatly be appreciated. The formulas I need are for the following:

Z Score which is the value -mean / the standard deviation

Midpoint which is (Lower class limit) + (Upper class limit)/2 (How to obtain
the lower and upper class limits in excel would also be appreciated)

Relative Frequency Which is Class Frequency/Sample Size (Also how to get the
class frequency and sample size in excel would also be appreciated.)

Weighted Mean which is The sum of (x*w)/n

Mean for Grouped Data which is the sum of (x*f)/n

Sample Standard Deviation for Grouped Data which is the Square root of the
sum of (x-xbar)^2*f/n-1

Chebychev's Theorem which is The portion of any data set lying within K
standard Deviation (k1) of the mean is at least :

(whole number 1) - 1/k^2 .

Thanks in advance for anyone who can help.