Does anyone here know anything about statistics?

I need help with working out 2 std dev and 3 std dev....

My brain is getting sore!

Do you have Excel? Put your values in a column, highlight the next cell, go to "Insert", select Function and then STDEV. That will give you one standard deviation. Simply multiply!

Thanks!

i just figured out what I was doing wrong. I was swapping around my calcs for Upper and lower control limits.

Problem is, when I write my exam - I won't have excel - so I am trying to do everything manually. But my brain isn't really a numerate one!

Thanks again.

Oooh, boy, manually! That's why I love Excel-it does all the hard work for me (and I'm NOT a statistician).

Lol.

Thanks!

Good luck on your exam! (I am an Excel user, too . . . you're braver than I am. )