Is this compounded daily, or is it compounded once at the end of the 195 days
(in which case wouldn't technically be compounded)? By "1 payment" I assume
you mean the entire pricipal is to be paid back after 195 days. I'll assume
compounded daily and entire principal paid @ t=195 days:
Amount paid Back = 57,310.37 * (1+ .03/365)^195 = $58,236.27
Resulting in $925.90 in interest paid (58,236.2757,310.37)
Does that help?

Regards,
Dave
"ROL" wrote:
> Principal amount is $57,310.38; interest is 3% per annum, length of time is
> 195 days with 1 payment at the end of the 195 days. I'm clueless as to which
> formula to use and what #'s to plug in. Hope someone can help.
