Does anyone know how to calculate the fold equity needed in mw pots? Ive heard of the method of if 2 players, say in the blinds fold 50% each. Then they would have a combined folding frequency of .5 x .5= 25%. But is that accurate?

I was wondering because i had a spot where a player had opened, BU 3b and i had AK and i estimated that with my pot equity had i got all in that i would have needed a fold abit more than 50% of the time. But was unsure as i had BB to act along with the other 2 players.