Do the math fuckin' peanut butter Share definition Flag figure it out yourself--it's easy, you dope-head ( see also: dtmfpb). person 1: How much do I owe you? person 2: Do the math fuckin' peanut butter Do the math fuckin' peanut butter by lucy 2 February 2, 2009 0 0 Get merch Get the Do the math fuckin' peanut butter mug. Buy Now — $32.95 See more merch