Answer One: Spot the Differences
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Answer Two: Two Guards
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Ask one guard, “What will the other guard say if I ask him, ‘Will Door A lead to paradise?’”
If the answer is “He will say ‘yes,’” then go to Door B. If the answer is “He will say ‘no,’” go to Door A.
Answer Three: Epitaph
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There are two widows, each with a son. Then each widow married the other’s son, and produced a daughter.
Answer Four: Connect the Dots II
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Answer Five: Finding a Birthday
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(To be announced! You guys need to attempt the problem before I can answer it.

)
Answer Six: Decode the Message
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Help me
Pi 14 means that pi to 14 decimal places (3.14159265358979) was used to cipher the message.
Each digit represents a letter in the alphabet: 1=a, 2=b, 3=c, 4=d, ….
So starting with the message “Help me,” digits were added to obscure the message …
HELPME
Add c (=3) after the third letter - HELCPME
Add a (=1) after the first letter - HAELCPME
Add d (=4) after the fourth letter - HAELDCPME
After the fourteenth decimal place, the message is HABCAEEGEIHILFEDCPIME. You need to have worked backwards.
Answer Seven: Urban Planning
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There are different solutions, but one ingenious solution is:
Answer Eight: Pigeons
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One remained: the one that died. The others flew away.
Answer Nine: Placing Queens
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Answer Ten: The Game of Know
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I know words that contain the letter i, but not words that don’t.