1. ## Variance

In a dozen eggs, the mean number of broken ones is .6
SD=.5 eggs

I expect to get 1.8 broken eggs.
Whats the SD?
I dont understand this...can someone please explain?
Id really appreciate it!

2. Originally Posted by Morgan82
In a dozen eggs, the mean number of broken ones is .6
SD=.5 eggs

I expect to get 1.8 broken eggs.
Whats the SD?
I dont understand this...can someone please explain?
Id really appreciate it!
The standard deviation scales as the square root of the number of cases.

There we have a SD of the number of broken eggs for 1 doz of 0.5, so the SD for 3 doz is (0.5)(sqrt(3))~=0.867

RonL

3. Originally Posted by Morgan82
In a dozen eggs, the mean number of broken ones is .6
SD=.5 eggs
$\sigma_n = \frac{\sigma}{\sqrt{n}} \Rightarrow \frac{1}{2\sqrt{3}} = 0.2887$