Your friend is right that:

if you can win $86 by only investing $40, you only need ~31% equity.

But remember, you only win $86 when UTG and MP

*both* call, so you have to compare your hand against 6% and 10% together and in that case your equity goes down. You said:

when I play I count only equity vs 6% because I know that vs 10% im ahead.

That's not right. If you go all in with AQ vs AJ you are ahead but you don't have 100% equity because opponent can still get a J - so you still have to count opponent's equity even if you are ahead.

Now, if you think UTG always folds then you only equilate against 6%, but then you only win $46 not $86. I.e. you can't have it both ways.

If you only win $46 then you need better equity - in this case 46.51% - which is the figure you mention.

So, if you can win more you need less equity. But if you win less, you need more equity. Simple.

edit: also, remember to include FE like whateverdude said.[/quote]