It depends on what Im drinking.
Lager, I seem to get drunk off about 3/4 pints. Cider is usually 3
Wine...obviously depends on how good the wine is. I have been known to get drunk off a glass and a half off some £40quid a bottle stuff my mother bought
Spirits, I can usually have round about 5 doubles or so and then am mortal...but sourz etc I can drink all night and they dont touch me.
But malibu...it takes about a large bottle