Which of the choices is the standard deviation of the sample shown here?

19, 20, 21, 22, 23

A. 2.5
B. 21
C.
D. 2
E.

Question

Which of the choices is the standard deviation of the sample shown here?

19, 20, 21, 22, 23

A.	2.5
 		B.	21
 		C.	
 		D.	2
 		E.

anonymous · Answer

Well you could just compute this

anonymous · Answer

i dont know how to. I'm SO lost

anonymous · Answer

what are C and E?

anonymous · Answer

oops. C is square root of 2.5, and D is square root of 2

anonymous · Answer

Do you know the formula for computing standard deviation?

anonymous · Answer

http://sonia.hubpages.com/hub/stddev

anonymous · Answer

i figured out the mean, and then guessed from there and it was C!

anonymous · Answer

I don't know know how you guessed C, but C is correct. 

The standard deviation has two different definitions. If the sample represents the entire population, the standard deviation is defined as$$\sigma = \sqrt{ {1 \over N} \sum_{i=1}^N (x_i - \mu)^2 }$$If the sample represents only a portion of the population, $$\sigma = \sqrt{ {1 \over N -1} (x_i - \mu)^2 }$$In this case, we can assume that sample represents the entire population.