She say she only fucked like 4-5 niggas, so you know you gotta multiply by 3

from J. Cole (Ft. Missy Elliott) – Nobody's Perfect Lyrics on Rap Genius

Meaning

Every girl lies about the dude’s they’ve gotten down with. FACT. So Cole is saying take whatever number she gives you and triple it (meaning this girl’s expected value of past sex is in the 12 — 15 niggas range.. not terrible..)

Stifler dropped this knowledge during American Pie 2:

When a girl tells you how many guys she’s slept with, multiply it by three and that’s the real number. Didn’t you fuckers learn anything in college?

They actually have a point though:

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