40% to call

hi all
i was reading an article and it mentioned someone
trying to figure out whether to call a river bet or not
they said they needed about 40% to call
where does this 40% figure come from ?
what calculations etc. ?
thanks for any help

The article meant you need to win the hand more than 40% of the time to show a profit longterm (not knowing for sure what your opponent has) in that situation. So you consider all the hands your opponent could have as the hand has played out (actions on every street can narrow the range of hands he has down) and decide/estimate whether your hand will be best 40%+ of the time versus the remaining possibilities/combinations.

A call that is breakeven at 40% would be if the pot was x and your opponent bet 2x, you would have to call 2x to win 3x. If 40% of the time you win 3x, and 60% you lose 2x you breakeven. (0.4 * 3) = (0.6 * 2)

This was on a river call where you either have the best hand or you don't. If you were calling all in on an earlier street, then someone that says you need 40% would be referring to your hand's equity against your opponents range with cards to come and that gets a little more involved. There are programs that can help with these calculations (I don't mean while playing)

thanks for reply m8
still a bit confused
gonna do a bit more research
i think its something to do with
putting villain on a hand range
strong % + bluff % = call %
or am i just complicating things ?
anyway thanks m8

yea, it comes down to comparing your opponents hand range (all hands that would make it to the river and then either bluff or value bet that amount) against your holding - decide whether your hand is better than 40% of that range...but the 40% threshold came from calculating the pot odds. Sorry, I was still editing my post when you replied.

ta m8
food for thought