Question

Here are the prices for 8 different MP3 players. Find the standard deviation.

$195 $358 $201 $276 $161 $301 $387 $128

Answer 1

The mean is 250.875.

Using this information, I can put the following into a calculator:
√(((250.875-195)²+(250.875-358)²+(250.875-201)²+(250.875-276)²+
(250.875-161)²+(250.875-301)²+(250.875-387)²+(250.875-128)²)÷8)

Which equals:
87.9878

This is the standard deviation of the MP3 players.