♟️ Strategy
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+16 points
#15
The Dark Room Drawer
⏳
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The solution goes up on 07 September. Send in your answer before then and it counts for full points — you will not be told whether it is right until the reveal.
A drawer holds 30 socks, jumbled together:
- 10 black socks,
- 12 white socks,
- 8 grey socks.
The power is out and the room is completely dark. You cannot tell the colours apart by touch, and once a sock is out of the drawer you may not put it back.
All the same to the hand. Only the count is on your side.
🌑You need two black socks — and you must be certain, not lucky. Assume the worst possible order of draws.
Answer to type: the smallest number of socks you must take out to be sure of holding two black ones.
💡 I want a nudge
Do not ask what is likely. Ask what the unluckiest possible hand looks like — and then take one more sock than that.
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