One way

=12^(1/2)*29.5

or

=STDEV(A1:A20)*12^(1/2)


--

Regards,

Peo Sjoblom


"Smiley" wrote in message
...
I have a row of percenteges (12) where I have to get the Standarddeviation
from,that number has to be multiplied with the root of 12