Just need some help solving this question, the "at least 3" instead of "exactly 3" makes this difficult, I'm not sure where to start.

Assume there are 8 bags in front of you, all containing marbles of varying colours. The probability, per bag, of randomly picking a red marble, for bags #1 through #7 is 2%, while the probability of randomly picking a red marble in bag #8 is 1%. What is the chance you will pick at least 3 red marbles, if you're picking exactly one marble from each bag, randomly?

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    $\begingroup$ Consider instead the probability of the complementary event (at most $2$ reds). You can case it as $$(0,0),(1,0),(0,1),(1,1),(2,0)$$ where the pair $(x,y)$ represents the outcome $x$ reds total from bags $1$ to $7$, and $y$ reds from bag $8$. $\endgroup$ – quasi Oct 12 '18 at 22:39
  • $\begingroup$ If you can't even start, begin by calculating the probability of drawing all red marbles. $\endgroup$ – samerivertwice Oct 20 '18 at 2:24

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