Michael Sylvester wrote:
> can anyone explain to me statistical expressions such as:
> 1 part in a billion.
> This caught my attention because of the discovery of arsenic
> in a number of playgrounds in the Central Florida area.
It isn't a standard statistical expression, Michael, it's a unit of
measure (albeit averaged in the sample). 1ppb (1 part per billion) simply
indicates that one out of every billion molecules in a given compound or
mixture contains a substance that the other 999,999,999 do not.
Rick
--
Rick Adams
Department of Social Sciences
Jackson Community College
Jackson, MI
[EMAIL PROTECTED]
"... and the only measure of your worth and your deeds will be the love
you leave behind when you're gone. --Fred Small, Everything Possible "
