1. ## ughh, need help!!

hours/ week.......12....32.....35.....38.....42 T=159
# of employees....1.....5.......7.......8......5 T=26
(x-mu)............-23.8..-3.8..-0.8...2.2....6.2
$\displaystyle (x-mu)^2$.......566.44...14.44...0.64...4.84...38.44 T=544.80

determine the mean, variance, and standard deviation for the nurse's hours

the mean is 35.8...

I need to know which equations to use for variance and standard deviation...
can someone show me the eq. needed to find each and (if there is) the sequence to find them?

2. Originally Posted by perron
hours/ week.......12....32.....35.....38.....42 T=159
# of employees....1.....5.......7.......8......5 T=26
(x-mu)............-23.8..-3.8..-0.8...2.2....6.2
$\displaystyle (x-mu)^2$.......566.44...14.44...0.64...4.84...38.44 T=544.80

determine the mean, variance, and standard deviation for the nurse's hours

the mean is 35.8...

I need to know which equations to use for variance and standard deviation...
can someone show me the eq. needed to find each and (if there is) the sequence to find them?
Do you not have class notes or textbook that give the forumulae and examples of how to use them?

3. yep, I have notes from class and I tried following the way my teacher did it but I can't seem to get the right answer!!

my attempt to write out the formula...

$\displaystyle 6= Ei fi (xi-x(with line))^2$
$\displaystyle Ei fi$

AND
$\displaystyle 6= Ei fi (xi-x(with line))^2$