Statistic help: PLEASE HELP

[Guest]

I need to find the mean and the median

The standard deviation is 5.816 min
The varience is 33.830 min squared
And the range is 25 minutes.
With a frequency of 40

the E(looking thing) Efx=715.0
and the Efxsquared= 14100.0

 

[tkhunny]

1) Frequency? That is the sample size, I hope.
2) The "e-looking-thing" is a sigma and it signifies summation.

You have (14100 - ((715²)/40))/39 = 33.83 the variance. You should have the formula for that.

Trivially, then 715/40 = 17.875 the mean. you should have the formula for that.