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# Pickett

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## Posts posted by Pickett

1. any number minus itself equals 0. Rule number 1 of basic subtraction. Good riddle!!

Ok, so, some people have already hinted at this in their answers...but I thought I would write my thoughts on this riddle down:

First of all, "Infinity" is NOT a number...as a result, subtraction is not clearly defined (as one poster said earlier). While it is true that any number minus itself equals 0, infinity is not a number. Hence, the basic rules of subtraction do not apply.

Infinity is an IDEA, or a concept. You cannot count to infinity...there is no "infinity plus 1"...It's funny that infinity is so hard for many people to wrap their mind around, since it truly is simpler as a concept than anything finite (since you don't have to define any boundaries...it's just infinite).

Let's say we wanted to try to treat this infinity as a number for this riddle...we can then prove that there are actually infinite answers to this equation:

Infinity - Infinity = INFINITY

1. There are infinite positive even numbers...so the sum of all positive even numbers is "infinity"

2. There are infinite positive odd numbers...so the sum of all positive odd numbers is "infinity"

3. There are infinite positive whole numbers...so the sum of all positive whole numbers is "infinity"

4. So, the riddle states infinity - infinity = ????. If we substitute we get "sum of all positive whole numbers minus sum of all positive odd numbers equals what??" And the answer to that would be "the sum of all positive even numbers"...which is INFINITY

OR Infinity - Infinity = 4

1. There are infinite positive whole numbers...so the sum of all positive whole numbers is "infinity"

2. There are infinite positive whole numbers that are NOT the number 4...so the sum of all these numbers is "infinity"

3. So, again, we subtract the sum of all the positive whole numbers that are not the number 4 from the sum of all the positive whole numbers, and we get 4 as our answer

OR Infinity - Infinity = 74629274739

1. There are infinite positive whole numbers...so the sum of all positive whole numbers is "infinity"

2. There are infinite positive whole numbers that are NOT the number 74629274739...so the sum of all these numbers is "infinity"

3. So, again, we subtract the sum of all the positive whole numbers that are not the number 74629274739 from the sum of all of the positive whole numbers, and we get 74629274739 as our answer

So, you can see that trying to apply "basic" mathematical operations to INFINITY is pointless...

Since infinity is an idea, or concept, the equation basically becomes "an idea - an idea = ???" which would be "no ideas" or "no thought"...

Therefore, my answer is either a completely mindless person or Nirvana (or some other Zen-like state in which there are no thoughts)

Even the title of this riddle "Number infinity" is essentially an oxymoron. I'm actually really hoping there is some twist or cool trick that the OP was intending (like the 818 answer that was given)...

"Two things are infinite: the universe and human stupidity; and I'm not sure about the universe." -Albert Einstein

2. S E V E N T Y

÷ S E V E N

-------------------

T E N

Only number not used is 5. Will tell how many times each number appears if necessary. Same letter doesn't mean same number.

Questions:

1. "Same letter doesn't mean same number."...so really, any of the letters can be any number (except 5)...right?

Basically if that's true, then the problem simply becomes, "find a 7-digit number, that when divided by a 5 digit number, yields a 3 digit number". Then there are plenty of solutions to this:

9000000 / 10000 = 900 for example...Not sure I understand your question...

3. This is the same as a riddle I posted not too long ago...see my answer (and others) here

4. Have two or three of me, I'll erase your frown

The more you have the more inhibitions go down

If you are staring at yourself it might not be too late

Don't whisper my name and you won't tempt fate

A nickname earned when religious dissenters I had burned

Catholicism is the best, I guess, was the lesson learned

Bloody Mary

5. Number 2 is wrong. The rest are correct. Go by how it sounds, not how it's spelled.

cough

6. 15
skinny puppy

Nice...the only one I didn't get...never heard of them. Well done

7. I know someone did something like this before. I thought it was fun, so I'd take a stab at it. I hope none of these are repeats. This is how it works, I'll give you some words, and you'll have to figure out the band name they describe. Ok, here goes.....

1. Squashing Jack-o-lanterns Smashing Pumpkins

2. Something long, measured in U.S. increments, that you pound into the wall Nine Inch Nails

3. Caucasian living dead White Zombie

4. The spawn, or children The Offspring

5. Obese kid skinny Fat Boy Slim

6. A vessel that goes under water + a green fruit Sublime

7. Buddhist state of enlightenment and tranquility Nirvana

8. Alabaster lines White Stripes

9. Oceanspray ingredient Cranberries

11.Smooch Kiss

13. 1-2-3-4-5... black birds Counting Crows

14. A shrubbery Bush

15. Slim young dog

8. change it so its:

5 - 3 = 2

(in matchstick form)

Since the original was

|||| + || = |||

and you're only allowed moving 1 matchstick...I don't see how you can get

||||| - ||| = ||

out of that (you'd have to move 2 matchsticks...1 from the plus to make it a minus, and one from the RHS to make it ||)...

but you can get

||||| - || = ||| (5 - 2 = 3)...so, you just had your numbers flipped...so good answer!

9. Since the OP doesn't specify HOW this needs to be done, I'm going to take the super easy way out for now:

Simply move any one match from the |||| on the LHS and put it on top of the equals sign to give you:

||| + || ≠ |||

So, 3 + 2 does NOT equal 3...voila, I moved one match stick to make it a completely valid mathematical equation.

10. There is a high-rise building in front of your house. You want to measure the building's height. Using common household items, list out the strategies to measure the building's height. (And no, common household items don't include laser measurement tool or a coil of rope as long as the building's height, though I guess watches with atomic accuracy are allowed).

This question (or a similar variation of it) is often asked during technical interviews for companies...I know for a fact it was asked in some interviews to work for Google, and I've been asked this questions a few times for other companies. Basically it's just to see how creative you can be and if you can think outside the box. The one I've always liked is the one already mentioned, which is bribe the doorman of the building to tell you the height.

The other variation I've been asked is, how many ways can you measure the height of the building with nothing but a barometer?...so, assuming you have a barometer around your house, it's the same question...Thanks for posting this one...it's fun to see what people come up with

11. nice job Pickett! Had you heard it before?

A piece of paper is an "ink-lined plane". An "inclined plane" is a "slope up". A "slow pup" is a lazy dog

Yeah, don't remember where I heard it, but I like that one.

12. 1. Because it can produce a few notes, tho they are very flat; and it is nevar put with the wrong end in front! (this quote was from Caroll himself in a preface to a later edition of his book...he spelled nevAr so that it is RAVEN backwards...but later editions mis-stated him and put "never" instead...although, I agree, his original riddle when he wrote it did not have an answer.)

2. Because the notes for which they are noted are not noted for being musical notes.

3. Because Poe wrote on both.

4. Because you cannot ride either one of them like a bicycle. (my favorite answer)

How is a piece of paper like a lazy dog?

A piece of paper is an "ink-lined plane". An "inclined plane" is a "slope up". A "slow pup" is a lazy dog

13. I must be really stupid. I just don't understand how you get that answer.

Just add consecutive digits of PI together

3.1415926535898..etc...

so 3 is the first number, then 3 + 1, then 1 + 4, then 4 + 1, then 1 + 5...etc...

14. Have nothing against Bellax... But it does have to do with something else mentioned there... You were closer on your first tries...

Yeah, the more I thought about it, the less it seemed to fit (with the pair of hands 9 and then 3...etc...) oh well, at least I got things on the right track...

15. In this land there are Mountains ("M" which if you make it upside down: "W"), to travel there you take a boat. ("e" upside down looks a bit like a boat...)

A pair of hands that point to 9 (maybe "9" upside down is "b" or "d"...not sure about pair of hands pointing though) will tka you to a hanger and coat. ("t" or "j" or "f" maybe)

These hands again now at 3, ("3" backwards is "E"...again, not sure about those hands) a twist of fate to a pirates glee. ("x" marks the spot?)

HAHAHAHA...if this is right, this is really funny!

You are BellaxPalus!! And I haven't read the specific incident, but I'm guessing it has to do with hurricanes??

My reasoning:

Mountains = B (turn it 90 degrees)...

Boat = e (upside down)

LL = hands pointing at 3

a = hangar and a coat

x = pirate's glee..

And I've noticed that you tend to get a bit worked up with BellaxPalus's riddles...

16. In this land there are Mountains, to travel there you take a boat.

A pair of hands that point to 9 will tka you to a hanger and coat.

These hands again now at 3, a twist of fate to a pirates glee.

In this land there are Mountains ("M" which if you make it upside down: "W"), to travel there you take a boat. ("e" upside down looks a bit like a boat...)

A pair of hands that point to 9 (maybe "9" upside down is "b" or "d"...not sure about pair of hands pointing though) will tka you to a hanger and coat. ("t" or "j" or "f" maybe)

These hands again now at 3, ("3" backwards is "E"...again, not sure about those hands) a twist of fate to a pirates glee. ("x" marks the spot?)

17. This is not a trick question. This is a real math problem so don't say that a bus has no legs.

There are 7 girls in a bus.

Each girl has 7 backpacks.

In each backpack, there are 7 big cats.

For every big cat there are 7 little cats.

The bus driver is not on the bus.

Question: How many legs are there in the bus?

This is a duplicate...(except the bus driver line is added in this one)

Expect this to be locked soon...

18. You ponder this over and over in your head. Mmmm. Sort of random. Starts with three. You're distracted momentarily by something cooling in the windowsill...

3 = 3

3 + 1 = 4

1 + 4 = 5

4 + 1 = 5

1 + 5 = 6

5 + 9 = 14

9 + 2 = 11

2 + 6 = 8

6 + 5 = 11

5 + 3 = 8

etc...etc...

19. Since you wanted to know what gave your riddle(s) away, here's my train of thought for this one:

Six of us you may see,

Ok, something that is made of six parts, or has six forms, or something along those lines

Running our narrow course.

Didn't really get anything from this line at first, but now get it

Enriching one's life beautifully,

Or expressing one's remorse.

Hmm...showing different emotions...broad range of exp​ression

Crossing ridge after ridge,

Voicing our motion and strain

This line really pointed to musical instrument with strings, because of STRAIN and VOICING MOTION

We have our end at a bridge

A bridge is a term for the base of where the strings attach to the body on most stringed instruments...

And hope we've entertained

More reason to believe musical instrument (entertainment)

So, since there were six of the strings, going over "ridges" (aka frets), and a bridge...it made it obvious it was guitar...but then you have to account for the fact that it is the STRINGS that are telling the riddle...so...the answer is Guitar Strings.

For me, I feel you used too many key words (bridge, strain, voicing our motion, entertain, ridge) which just having those words alone point to a guitar. I would maybe suggest more misdirection (like the first line being "four, five, six, or seven of us there could be" or something like that) or even telling a story with them (like "we traveled over many hills, each one looming closer than the last until we finally had to cross a bridge. Our tense journey was finally over...blah blah blah)...I obviously didn't put it to rhyme in this example, but you get the point...

I like your riddles though, so keep it up!

20. You are right...you just shoot 'em down as I throw 'em up. Nice work! Could you maybe tell me what gave my last two away so easily? Haha...

Four walls, with halls, a fortress of sorts

This place, a space, is known to time, distort.

Someplace where you lose track of time

Tables, chairs, and lights may be found,

umm...pretty self explanatory

When you come to have a look around.

Ah, someplace intellectual...

Many a person, their boredom is worsened

Some people are bored at this place

Come if you need information, accurate

A building that contains a lot of information...

But only if you won't procrastinate.

Typically procrastination is with regards to an assignment or homework of some sort...again, academic

So, put all of them together, you get a library. It's very well written, and there isn't ONE line that gave it away...You are just much too literal with many of the lines, and you give a lot of different clues. Basically, if you wanted to make them harder, maybe just more symbolism, plays on words, double meanings, etc (read shakeepuddin's riddles for great examples)...I'll comment on the other one of yours I did earlier in that post...

Good job, keep it up.

21. Ok that last one was way too easy...let's try try try again.

Four walls, with halls, a fortress of sorts

This place, a space, is known to time, distort.

Tables, chairs, and lights may be found,

When you come to have a look around.

Many a person, their boredom is worsened

Come if you need information, accurate

But only if you won't procrastinate.

Name it.

a library?

22. You are correct! Wow, that didn't last long...

That I enjoy playing guitar...and so this naturally came to me pretty quickly :c)

23. Here's my riddle for today...might be easy. Please give feedback!

Six of us you may see,

Running our narrow course.

Enriching one's life beautifully,

Or expressing one's remorse.

Crossing ridge after ridge,

Voicing our motion and strain

We have our end at a bridge

And hope we've entertained

What am I?

Guitar or some other six-stringed instrument...specifically one with frets (or other ridges), and ending at a bridge....the strings are under great strain on the neck of the instrument and they entertain and can express happiness or remorse...actually, re-reading, I revise my answer to be GUITAR STRINGS :c)

24. cant find the answer on the internet but is it

Is it that (money/coins) were not (dated/in use) during 500bc and didn't happen until much later in human history

No...

They couldn't have known it was "BC" since "BC" didn't exist until after year 0/1/-1/whatever...so in 500BC, they wouldn't have dated their coins with "BC" on it....just like with the sword, they wouldn't have called it World War 1, since they didn't know there would be a 2

25. Indeed, 46464, 69696 are the only possible positive decimal palindromes that satisfy the given conditions.

However, I do not know of an easy analytic method (and still looking for it) to substantiate this.

Notes:

1. It may be observed that a palindrome is always an integer according to this mathworld article , unless stated otherwise.

2. According to wikipedia, decimal denotes base ten.

In hindsight, I should have mentioned “base ten representation……” in the problem text rather than “decimal representation”.

I wrote a simple little program to solve this problem... And I knew the upper bound for the number was 70710, since any number greater than that would have more than 10 digits in the resulting answer (which invalidates the requirement that all numbers be present in answer)...same with the lower bound being 22360 (since the resulting number would have less than 10 digits). See the attached code:

List<String> palindromes = getPalindromes(22360, 70710);
for (int i = 0; i < palindromes.size(); i++) {
Long l = Long.valueOf(palindromes.get(i));
Long newVal = 2 * (l * l);
String newStr = newVal.toString();
boolean hasAll = true;
for (int j = 0; j < 10; j++) {
if (newStr.indexOf(Integer.toString(j)) < 0) {
hasAll = false;
break;
}
}
if (hasAll) {
System.out.println(l + ": (2 * " + l + " * " + l + ") = " + newStr);
}
}
}

private static List<String> getPalindromes(long lowerBound, long upperBound) {
List<String> palindromes = new ArrayList<String>();
for (long i = lowerBound; i <= upperBound; i++) {
String val = Long.toString(i);
boolean isPal = true;
for (int j = 0; j < val.length(); j++) {
if (val.charAt(j) != val.charAt(val.length() - (j + 1))) {
isPal = false;
break;
}
}
if (isPal) {
}
}
return palindromes;
}
`    public static void main(final String[] args) {`

Basically just get all numbers that are palindromes between those bounds, and then go through each of those palindromes, perform the operation, and check to make sure each resulting answer has every number. Fun problem, I enjoyed it.

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