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# bonanova

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1. ## Poisonous apples

The OP does not say how many apples there are. It says the proportion that are poisonous. Question: was that the intent?

Yes. .
5. ## Squares on a plywood

Doctoring the figure a bit (while I think about solving it.) o - o - o - o - o | / o o o o | / o - o - o Question: You mention the number of nails (12) and also the number of nails in the perimeter (here that's 10.) So for this example, would we be given N=12 or N=10? I'm thinking the latter, but would like to confirm.
6. ## 9-Balls Cue

Welcome back TSLF. Nice puzzle!

Looks like
9. ## Walk the pattern

With that interpretation,
10. ## Walk the pattern

Assuming the above, we note that
11. ## Walk the pattern

Just to be clear, n = 3 4 5 7 8 9 11 12 13 ..., and CW and CCW alternate untethered (my new favorite word) to parity?
12. ## Twins birthday puzzle

Nice solve. And the "few years back" is actually two years ago, when Feb 28 was Sunday and March 2 was Wednesday.
13. ## Strange math problem

The professor writes a problem on the whiteboard, thus: 25 - 55 + (85 + 65) = ? He then inexplicably states that, even though you might disagree, the correct answer is actually 5! Explanation?
14. ## Twins birthday puzzle

A few years back while visiting friends, we celebrated the birthdays of their identical twin daughters Joan and Jane, born just 5 minutes apart. Joan had her party on Sunday, and Jane had hers on Wednesday. Explanation?
15. ## Random passengers

This was my take.
16. ## Random passengers

Nice. One thing I liked about this puzzle is that it's open to clear thinking. Even tho at first it seems too complex.
17. ## Comparing a rectangle to a circle

But actually ...
18. ## Comparing a rectangle to a circle

It certainly should. It clearly fails a units check. Good catch.
19. ## Poisoned Needles

Do any of the clues imply that the indicated needles are adjacent? I would take "on the left side of" to imply that "pain" is adjacent to "seek," while "to the left of" simply means "the other pain" is not to the right of "interesting little creation." But I'd like to be certain of that. Also, is "interesting little creation" one of the needles? If so, you have described nine, not eight, needles. Thanks.
20. ## 100 coins. Some of them are fake

You have 10 sets of ten coins. One set of the ten is counterfeit, the others are genuine. The genuine coins weigh exactly 0.10 ounces. The counterfeit coins are exactly a 0.01 ounces off, making the entire set of ten coins 0.10 ounces off. You may use an extremely accurate digital scale only once. How do you determine which set is counterfeit?

Clue.
23. ## Two boys

@ThunderCloud you're homing in on it, but now you're a little high. @BMAD It's certainly true that if the FIRST child was a boy born on a tuesday, then it's just the prob that the second child is a boy. But ... the OP does not tell you that. That is, "one is a boy" does not imply "my oldest child is a boy." So your "second" child simply means the "other" child.
24. ## a^b x c^a = abca

Not that I know of. Tables of powers, or spreadsheet where different abc values can be simply typed in, or inspired guesswork? It's not my fav type of puzzle, but some like this type.
25. ## Two boys

@ThunderCloudThat's close, but a bit low.
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