Hi folks

Just starting - nice site. My topic to learn today is betting for value. Can someone run me through an example.

Limit hold'em, I have a nut flush draw on the flop. So thats 9 outs out of 47 cards. 4 opponents say, at first glance seems if I bet (and they all call) I need to win 1/5 of the time to break even. So 4 is not enough, but 5 is maybe. I guess implied odds is something that comes from experience. Whats the true answer, 3 opponents? Can someone run through the maths for me so I know how to do these things.

Tx