To push or not to push

[Lee_C]

I'm trying to find out how often my opponent has to fold in a given situation for an all in semi-bluff to be profitable.

This is the situation:

The current pot contains 10000.
I have 8500 left behind.

I have exactly 11 outs on the turn and hence a 25% equity.

I push.

The Ev of a call would be (0.25 x 18500) - (0.75 x 8500)
EVcall = -1750

However, if my opponent folds often enough this should be a +EV play.

So to make a break even situation, I set the EV to 0 and solve for the Fold % which I call F.

So I get the equation:
0 = (Fold% x Current Pot) + (Call % x EVcall)
0 = F x(10 000) + (1-F)x(-1750)
0 = 10000F + 1750F - 1750
1750 = 11750F
F = 1750/11750
F = 0.1489 or 14.89% for the play to be break even.

Is this the correct method for solving this problem?