Pot Equity and Pot Odds

[twain]

I recently read that pot equity can help one see how much they are giving up by folding by considering the number of bets in a pot and one's number of outs (or % of time that draw will come in). For example, if you have a draw that will come in 12.5% of the time and a pot that has nine bets in it, your pot equity can be equated to 1.125 bets (.125 x 9). Since 1.125 is greater than 1.00. It seems that there is reason to call one more bet (since it is less than the equity already invested in to the pot). Pot odds and implied odds though may dictate that I fold though because my expectation of hitting an out are less than what I stand to gain from winnning the pot. I assume thus that the correct answer would be to fold. Is this correct? Or more to the point, in general are there circumstances where I should call instead of fold based on the equity of the pot instead of on the pot and implied odds I'm receiving?