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# bonanova

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## Posts posted by bonanova

1. ### International Football Team

Spoiler

The Selection pool comprises 20 players: { SS III FFFF BBBBB GGGGGG }
Removing the captain and goalkeeper the pool shrinks to 18:
{ SS II FFF BBBBB GGGGGG }
Without the three-German restriction, we have 18 choose 9 =
48620 different teams.

We must include {3 4 5 6} Germans, then choose {6 5 4 3} from the 12 non-Germans.

(6 choose 3 = 20) x (12 choose 6 = 924) = 18380
(6 choose 4 = 12) x (12 choose 5 = 792) =  9504
(6 choose 5 =  6) x (12 choose 4 = 495) =  2790
(6 choose 6 =  1) x (12 choose 3 = 220) =    220
--------------------------------------------
TOTAL                                  30994 different teams

2. ### Matching cards

A deck of cards is shuffled and dealt face up in a single row. A second deck is shuffled and dealt face up in a single row beneath the first row, making 52 coloumns each containing two cards. On average, how many pairs of cards will match?

3. ### Singular plurals

On 4/22/2019 at 3:07 AM, Wilson said:

Related...........well maybe

Reveal hidden contents

Well done @Wilson!

4. ### Finally the AG he needs ...

Attorney General Barr was seen in Washington yesterday wearing a custom made cap with the initials M.A.G.A. For his cap they meant Make Allegations Go Away.

5. ### Walking, running, driving, waiting

On 4/21/2019 at 1:27 PM, Thalia said:

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Well, depending on whether you're rounding down or are actually going exactly 0 mph... "I won't be home tonight."?

I'll accept it but I was thinking more like ....

Spoiler

I won't be home .... forever!

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6. ### Walking, running, driving, waiting

With a tip of the hat to @BMAD  for his interesting puzzle.

For your amusement, here's an interesting spin on this genre:

One night you encounter a two-hour traffic delay due to an accident (the tow truck had difficulty clearing the road.) So, for a time interval 13 of two hours you were constrained to travel at 0 mph. You called home and said, sorry dear, but I'll be two hours late getting home.

The next night, for some unimaginable reason, you were also constrained to travel part of the way at 0 mph, this time for a distance of one inch. What do you say now when you call home?

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7. ### Singular plurals

On 4/2/2019 at 12:50 AM, Thalia said:

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Does the 2nd word have to be the plural of the 1st word or can it be a different word?

"Becomes plural by removing it." Could that mean removing the letters "i-t"?

I'll answer both in the clear.

No. (although the words I have in mind, one plural, one singular, are closely related)

No. It's the literal removal of an "s".

On 4/2/2019 at 7:02 AM, rocdocmac said:
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brass - s = bras

Playing with singulars and plurals I arrived at these facts ,,,

If the plural of mouse is mice and that of louse is lice,  then the plural of house must be hice and the singular of rice must be rouse.

Kudos. But not the words I had in mind. They are common words, and they are closely related.

8. ### The liar, the truth teller....and the random answerer

@Jaspreet Singh greetings and welcome to the Den.

2007 really? Twelve years ago? This puzzle is a time capsule.

9. ### Fair division of sausages

Appears to be ...

Spoiler

Simplify to dividing 5 sausages for 3 people

Denote a third of a sausage (whether cut or uncut) by [3].
Denote an uncut sausage by [3][3][3] and an intact 2/3 of a sausage by [3][3].

Three persons would be optimally served as follows:

1. [3][3][3]  [3][3]
2. [3][3][3]  [3]  [3]
3. [3][3][3]  [3][3]

The black sausages were not cut.
Two sausages, the red one and the green one, were each cut once, creating four pieces.

Do this 6 times.

12 cuts will have created 24 pieces.

10. ### Easy Root

The solutions are

Spoiler

1 and 2.

Because

Spoiler

x 1/x = (x2)1/x^2 = x 2/x^2

By inspection 1 and 2 are solutions, and a plot of the difference of x 1/x and x 2/x^x shows sign changes (only) at 1 and 2.

Also, for any value of x not equal to 0 (illegal division) or 1 (all powers of 1 are equal) dividing by x yields simply

1/x = 2/x2 or more simply

x2 = 2x.

Cute.

11. ### Question

Not in every case.

You could be kept alive from nourishment by other means. An intravenous tube, for example.

So there is hope, and you can smile once again.

12. ### Singular plurals

That's the one I had in mind.

13. ### Singular plurals

Many singular English nouns are made plural by adding a trailing "s".

Name a singular noun with a trailing "s" that becomes plural by removing it.

Name a singular noun that is made plural by adding a "c".

14. ### A physicist, a biologist, and a mathematician are sitting on a bench

A physicist, a biologist, and a mathematician are sitting on a bench across from a house.
They watch as two people go into the house, and then a little later, three people walk out.

The physicist says, "The initial measurement was incorrect."

The biologist says, "They must have reproduced."

And the mathematician says, "If exactly one person enters that house, it will be empty."

16. ### 13 BRAIN TEASERS TO MAKE YOU THINK HARD AND TO BOOST YOUR BRAIN POWER

Spoiler

1. Five.

2. If he were the fastest and slowest, there would be 1 runner. Add 49 in front and behind and you have 99 runners.

3. Clues 1 and 2 eliminate 0, and Clue 4 eliminates 8. So Clue 1 establishes --2.
Clue 3 says 2 and 6 are correct but wrongly placed. So we have 6-2.
Clue 2 says ( 1 or 3 ) is correct ( so it's 612 or 632 ) but wrongly placed, so it's 632.

4. 3 sons, 4 daughters.

5. Ninth.

6. Nine. Or Ten.

7. Bruce and Frank are dead. Jack is alive.

8. 2 men (\$6), 5 women (\$7.50), 13 children (\$6.50)

9. Six. If they were all women.

10. Push the cork into the bottle. Shake the coin out.

11. (T)(e)(n)(H)(o)(r)(s)(e)(s)

12. Ten minutes

13. \$20

17. ### 12 RIDDLES THAT WILL TRICK YOUR MIND

I'll give these a shot.

Spoiler
1. x=10a; 2a=8; x=40
2. Beggar is a girl.
3. 50.
4. Fifth man was driving a car.
He originally outpaced the others until they ran and caught up at their destination.
5. 80 = 60+20.
6. He took a marble with his closed fist while pointing to the jar for his pick.
He then exposed a black marble in his hand, meaning his pick was a blue marble.
7. You will hang me.
8. Move the cat and come back. Move the mouse and retrieve the cat. Move the dog and come back. Move the cat.
9. Suffocation. Two goldfish.
10. No smoke from an electric train.
11. For sleeping on the job.
12. No. Fuel weighing more than the bird had been consumed before it landed on the truck.
18. ### Logic Puzzle with 26 Variables

Hi Tomson, and welcome to the Den.

Spoiler

Not much at all.

An oldie but goodie.

19. ### I'm not a bird

Poe, E. Near a Raven

Midnights so dreary, tired and weary.
Silently pondering volumes extolling all by-now obsolete lore.
During my rather long nap -- the weirdest tap!
An ominous vibrating sound disturbing my chamber's antedoor.
'This,' I whispered quietly, 'I ignore.'

- Mike Keith, 1995

20. ### Rodent Riddle

I watch word riddles in awe from the sidelines cuz my brain is wired deductively rather than inductively.
On this one, tho, as a musician of sorts, I have to say, bravo!
Great riddle and great solve!

21. ### Bowling for equilateral triangles

OK thx.

Spoiler

Then I'm guessing it's a lateral puzzle.  Thinking ...

22. ### I might be a writer

15 hours ago, Wilson said:

Best I've got......

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2^8 kinda hints at 2^B  .....so is it ....2B or not 2B?  William Shakespeare?

That's the answer I'm looking for. If you put your two posts together, you've got it.

Spoiler

FF?

1. What does FF? mean?
It clearly means "FF" is the question.

2. Seriously. What does "FF" mean?
Hex numbers have digits { 0 1 2 3 4 5 6 7 8 9 A B C D E F } with values 0-15 and
binary representations { 0000 0001 0010 0011 0100 0101 0110 0111 1000 1001 1010 1011 1100 1101 1110 1111 }.
That said, FF can be expressed as 1111 1111.

3. I'm waiting for something useful
OK. Now we have to do some reverse engineering.
Recall that 2 (hex) is 0010 and B (hex) is 1011?

4. *Tapping fingers*
Almost done.
In binary logic, "not" changes 1 (true) to 0 (false) and vice versa.
And "A or B" is true if either of A or B is true.

5. Seriously dude. This was a word riddle?
OK I could have posted it in the logic puzzle thread.
But you solved it, didn't you?

6. If you say so, but I don't see
2B = 0010 1011.
Not 2B = 1101 0100.
(2B) or (not 2B) = 1111 1111 = FF.
That, as we have just shown, is the question.
And Willie S. just might be a writer.
Very nice solve.

23. ### Brain Teaser

4 hours ago, Thalia said:

I think the inclusion of the word "who" indicates it applies to the American. Can't be sure without clarification though.

Agree.

If "Heidi" is the intended subject of "found," a 2nd "who" would serve no purpose except to confuse. It would not be used. Instead,

Heidi is { immediately right of (Person A) } and found { more caches than (Person B) }.

But since there are two "who"s, it's proper to bind them to the same (and closest) antecedent:

..... (Person A) { who has flown ... } and { who found more ... }

7) Heidi is immediately right of the person who has flown over from the States, and who found more caches than the UK cacher. 40 Traditional cache where found by a European cacher, their favourite type.

19 hours ago, rocdocmac said:
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(5) The Chilean, who is NOT "next door but one to the Belgian" therefore means that there is NOT one ﻿pitch between the Chilean and the Belgian.

Agree. They could not be Pitches 3 and 5, for example.

I also fixed a typo in my interpretation post.

24. ### Square Free

Clarification:

Spoiler

Do you agree the pieces at { e1 c3 g3 e5 } form a square?

25. ### Bowling for equilateral triangles

Spoiler

Does this have anything to do with Ramsey theory?

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