On Sun, 25 Oct 2009 13:00:04 -0700, cdh625
wrote:

She has $20,000 to invest today at 9% to pay a debt of $47,347. How many
years will it take her to accumulate enough to liquidate the debt? I tried
NPER and got an error. How do I use this function properly?

Did you get the #NUM! error?

If so, most likely you did not follow the conventions regarding SIGN of the
data. In particular, PV and FV need to have different signs.

=NPER(9%,0,-20000,47347)
--ron