Find the variance.
35, 35, 36, 36, 36, 37, 38, 40, 41, 41, 41, 43, 44, 47, 50, 50

Question

Find the variance.
35, 35, 36, 36, 36, 37, 38, 40, 41, 41, 41, 43, 44, 47, 50, 50

amistre64 · Answer

find the mean

subtract the mean from every data point

square the results and add them up

anonymous · Answer

Attached is the problem I tried to solve.  But, when I check my answer, it's wrong.  What am I doing wrong?

amistre64 · Answer

well lets check the mean for starters :)

anonymous · Answer

My mean is 15

amistre64 · Answer

so you mean to tell me that the mean is lower than the range ?

amistre64 · Answer

mean=325/8

anonymous · Answer

40.6

amistre64 · Answer

yep; and is this a population or sample?

anonymous · Answer

sample

amistre64 · Answer

then n-1 is fine for that part

anonymous · Answer

ok.

amistre64 · Answer

you doing the calcs by hand or got a ti83 on it?

anonymous · Answer

by hand.  I don't have a TI calc

amistre64 · Answer

http://www.wolframalpha.com/input/?i=+35%2C+35%2C+36%2C+36%2C+36%2C+37%2C+38%2C+40%2C+41%2C+41%2C+41%2C+43%2C+44%2C+47%2C+50%2C+50 square the standard deviation for variance :)

amistre64 · Answer

but yeah, get the mean .... not some made up number ; subtract it from the data points; or subtract the data points from it; and square the results' then add up the results and divide by n-1 for sample data

anonymous · Answer

I have attached how I worked it out.  I think, thats what I did.  Not sure, where I went wrong