>>508022319
I's not a 50/50 coin flip. It’s a Bayesian problem; updating probabilities based on evidence.

Drawing a gold ball is more likely if you were in the GG box (2 chances out of 2)

Drawing a gold ball is less likely if you were in the GS box (1 chance out of 2)

So, seeing a gold makes it twice as likely you're in the GG box.

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