No.11786712 ViewReplyOriginalReport
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You pick a box at random first. Then you always pull a gold ball out of it. Imagine there were a thousand silver balls with the one gold ball in the middle box in the picture. Every time you pick that box, you pick the one gold ball. If you pick that box and don't pull out a gold ball out of it, it doesn't count. Seeing into the boxes doesn't change a thing, this is abstract math. For each time you pick a different gold ball from the gold balls only box, you have picked the same gold ball from the lonely gold ball box again and again. Let's make this experiment in real life, with 5 gold balls in one box vs 1 gold ball in another box. You pick a box and then you pull a gold ball out of it. What is the chance there is another gold ball inside?