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(14.2) Binomial Distribution

Rolling 3 dice

Consider an experiement where you roll 3 dice. Let $X$ be the number of ones rolled. alt-text

$X=0$
If zero 1s are rolled, not 1 must be rolled on all three dice. alt-text
The probability of rolling [not 1]-[not 1]-[not 1] is $\biggl($