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Started by The Golden Touch, November 10, 2011, 11:05:26 AM

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The Golden Touch

So I've already posted this for one of my group games to figure out. This math problem was given to me via an AD at work.

7 girls on a bus.
Each girl has 7 bags.
Each bag has 7 cats.
Each cat has 7 kittens.
How many legs are on the bus?

The answer is not, "Buses don't have legs."


Also- feel free to post your own brain teasers!

"Yesterday was the easy day."
Ideas (Open) /What Floats My Boat\ Absences

Caeli

I love math problems. ♥

7 girls x 7 bags = 49 bags
49 bags x 7 cats each = 343 cats
343 cats x 4 legs each = 1372 cat legs

343 cats x 7 kittens = 2401 kittens
2401 kittens x 4 legs = 9604 kitten legs

7 girls x 2 legs = 14 girls' legs
1372 cat legs + 9604 kitten legs + 14 girls' legs = 10990 legs.

The answer is 10992 legs.
ʙᴜᴛᴛᴇʀғʟɪᴇs ᴀʀᴇ ɢᴏᴅ's ᴘʀᴏᴏғ ᴛʜᴀᴛ ᴡᴇ ᴄᴀɴ ʜᴀᴠᴇ ᴀ sᴇᴄᴏɴᴅ ᴄʜᴀɴᴄᴇ ᴀᴛ ʟɪғᴇ
ᴠᴇʀʏ sᴇʟᴇᴄᴛɪᴠᴇʟʏ ᴀᴠᴀɪʟᴀʙʟᴇ ғᴏʀ ɴᴇᴡ ʀᴏʟᴇᴘʟᴀʏs

ᴄʜᴇᴄᴋ ❋ ғᴏʀ ɪᴅᴇᴀs; 'ø' ғᴏʀ ᴏɴs&ᴏғғs, ᴏʀ ᴘᴍ ᴍᴇ.
{ø 𝕨 
  𝕒 }
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»  ᴄʜᴏᴏsᴇ ʏᴏᴜʀ ᴏᴡɴ ᴀᴅᴠᴇɴᴛᴜʀᴇ: ᴛʜᴇ ғɪғᴛʜ sᴄʜᴏʟᴀʀʟʏ ᴀʀᴛ
»  ひらひらと舞い散る桜に 手を伸ばすよ
»  ᴘʟᴏᴛ ʙᴜɴɴɪᴇs × sᴛᴏʀʏ sᴇᴇᴅs × ᴄʜᴀʀᴀᴄᴛᴇʀ ɪɴsᴘɪʀᴀᴛɪᴏɴs

The Golden Touch

Yay, Caeli! You super rock! I forgot to tell you not to count the bus driver but you got it either way. Now we need a new problem!

I figured mine out by single bag x seven + 14 legs.

"Yesterday was the easy day."
Ideas (Open) /What Floats My Boat\ Absences

Caeli

#3
Oh! I figured the bus driver would be the "forgotten" part of the puzzle... I always leave them out. :P

Here's two logic puzzles, one hard and one easier:




Four students took a test where every question had two possible answers, A or B. Each question was worth 10 points, for a total of 100 points.

The students' test results were posted as seen below, but the teacher forgot to tally Colin's score. Colin was heading to the teacher's office when Mary called him back, saying they could figure out his score using teh results from the other tests. Can you figure out Colin's score?



# MaryDanLisaColin
1
2
3
4
5
6
7
8
9
10
Score
B
B
A
B
A
B
B
A
B
B
70
B
A
A
A
B
A
B
A
A
A
50
B
A
A
A
B
B
B
A
B
A
30
B
B
A
A
A
B
B
A
A
A
?




A girl takes her dog out. At first, she carries her dog for 10 seconds, but then her dad steps out. At this point, the girl sets her dog down and keeps walking. The dog immediately runs over to the dad, and upon reaching him, he turns around and runs back to the girl. The dog keeps doing this until the dad catches up with the girl.

The dog runs at five feet per second, the dad walks at two feet per second, and the girl walks at one foot per second. How far does the dog run by the time the dad catches up to his daughter?
ʙᴜᴛᴛᴇʀғʟɪᴇs ᴀʀᴇ ɢᴏᴅ's ᴘʀᴏᴏғ ᴛʜᴀᴛ ᴡᴇ ᴄᴀɴ ʜᴀᴠᴇ ᴀ sᴇᴄᴏɴᴅ ᴄʜᴀɴᴄᴇ ᴀᴛ ʟɪғᴇ
ᴠᴇʀʏ sᴇʟᴇᴄᴛɪᴠᴇʟʏ ᴀᴠᴀɪʟᴀʙʟᴇ ғᴏʀ ɴᴇᴡ ʀᴏʟᴇᴘʟᴀʏs

ᴄʜᴇᴄᴋ ❋ ғᴏʀ ɪᴅᴇᴀs; 'ø' ғᴏʀ ᴏɴs&ᴏғғs, ᴏʀ ᴘᴍ ᴍᴇ.
{ø 𝕨 
  𝕒 }
»  ᴇʟʟɪᴡʀɪᴍᴏ
»  ᴄʜᴏᴏsᴇ ʏᴏᴜʀ ᴏᴡɴ ᴀᴅᴠᴇɴᴛᴜʀᴇ: ᴛʜᴇ ғɪғᴛʜ sᴄʜᴏʟᴀʀʟʏ ᴀʀᴛ
»  ひらひらと舞い散る桜に 手を伸ばすよ
»  ᴘʟᴏᴛ ʙᴜɴɴɪᴇs × sᴛᴏʀʏ sᴇᴇᴅs × ᴄʜᴀʀᴀᴄᴛᴇʀ ɪɴsᴘɪʀᴀᴛɪᴏɴs

Jacqueline

I will leave you two classics, as a tip I will give bonus points for guessing in which movie they appear. Enjoy!

As I was going to St Ives

I met a man with seven wives

Every wife had seven sacks

Every sack had seven cats

Every cat had seven kittens

Kittens, cats, sacks, wives

How many were going to St Ives?




You are given a 5 gallon jug and a 3 gallon jug in front of a fountain. Measure out exactly 4 gallons of water.

warlko

hi, I'm new here and I like brain teasers besides role play.


Caeli I think your first problem is incomplete. It's impossible to figure out colin's score without knowing others' score.
now in second problem the daughter is 10 feet ahead, and her dad is closing the distance at a rate of one foot per second so he'll catch up in 10 seconds. With the speed of 5 feet per second the dog will run 50 feet.


Elenwe your first problem may have several answers.

It does not tell where others are going so the answer might be 1 (only the teller)

If we assume all are going to St Ives then
persons = 9
       sacs = 7*7    = 49
       cats = 7*49   = 343
   kittens = 7*343 = 2401

        Total = 2802

If we count only Kittens, cats, sacks, wives then = 2800

If we discount sacs then = 2753 (including the teller)

In the second problem
First I'll fill 5 gallon jug and and then I'll pour the water from the 5 gallon jug into the 3 gallon jug after that I'll empty the 3 gallon jug and then I'll pour the remaining 2 gallon water from the 5 gallon jug into the 3 gallon jug. Now the 3 gallon jug will be able to hold additional 1 gallon water. Now I'll again fill the 5 gallon jug and pour 1 gallon in the 3 gallon jug so that I'll have 4 gallon water in 5 gallon jug.

Jacqueline

Hah! That's the fun thing about riddles, there is only one valid answer so you have to choose!

warlko

In that case I'd go for 1 (only the teller)

Jacqueline

I can't say if that's correct or not because in case that it was... it would be a spoiler for other people!

So... maybe yes, and maybe no!

Caela

Quote from: Elenwe on November 11, 2011, 05:44:44 AM
I will leave you two classics, as a tip I will give bonus points for guessing in which movie they appear. Enjoy!

As I was going to St Ives

I met a man with seven wives

Every wife had seven sacks

Every sack had seven cats

Every cat had seven kittens

Kittens, cats, sacks, wives

How many were going to St Ives?




You are given a 5 gallon jug and a 3 gallon jug in front of a fountain. Measure out exactly 4 gallons of water.

Only the teller is going to St. Ives.

The jugs have been explained and both are riddles given to Detective John Mclain and Zues (love Samuel Jackson!) in one of the Die Hard movies...believe it was the third.

warlko

hah! now I've to wait for another thing besides approval..

I've a conundrum...

Four cars are stopped at a four-way intersection. At the same time and at the same speed, they all drive forward and continue their journeys without colliding.
How is this possible?

NOTES:
All the cars are facing forward into the intersection.
The intersection is not large enough for the cars to
cross at the same time and miss each other
(this is possible on larger intersections).
There are no tricks such as overpasses or tunnels.

Jacqueline

Quote from: Caela on November 11, 2011, 11:25:12 AM
Only the teller is going to St. Ives.

The jugs have been explained and both are riddles given to Detective John Mclain and Zues (love Samuel Jackson!) in one of the Die Hard movies...believe it was the third.

Bonus points for Caela!

Shiny

Hey,


I also do believe that the scoring-riddle is unsolvable without the scores of Mary, Lisa and Dan,
(which to admit took me about three accumulated hours, spent with different approaches,) as long as guessing isn't an option. This way, I can only tell the maximum difference in scoring between each of them.


   
   
   
   
   
NameMaryDanLisaColin
Mary0643
Dan6023
Lisa4203
Colin3330

and that there are four answers they have in common, so between 0-40 points as an lower limitation.




I assume by large intersection you mean one with multiple lanes, warlko? So only two lanes crossing each other? And they all are driving straight forward , no meddling with the steering wheel?
No idea.



My puzzle:
There is an series of 100 numbered lamps, standing in line, and a 100 frogs.
When the lamps are touched they go off (if they were on) and vice versa.
At first, all lights are off.
The first frog jumps on every lamp and switches them on.
The second frog jumps on every second lamp and switches it off (so lamp nr. 2,4,6,... are now off).
The third frog jumps on every third lamp and switches it off/on (depending on its previous state).
And so on.
Which lamps remain on after all 100 frogs had their turn?
(And as a bonus question, if there was an infinite series of lamps and an infinite supply of frogs, how could the set of shining lamps be characterized?)


Have fun,


Shiny

Nothing great, but for someone to share their thoughts.

Caeli

Oops! Sorry about that, I typed up the whole thing and then forgot to include their test scores. :P

Quote from: Caeli on November 10, 2011, 11:52:56 AMFour students took a test where every question had two possible answers, A or B. Each question was worth 10 points, for a total of 100 points.

The students' test results were posted as seen below, but the teacher forgot to tally Colin's score. Colin was heading to the teacher's office when Mary called him back, saying they could figure out his score using teh results from the other tests. Can you figure out Colin's score?



# MaryDanLisaColin
1
2
3
4
5
6
7
8
9
10
Score
B
B
A
B
A
B
B
A
B
B
70
B
A
A
A
B
A
B
A
A
A
50
B
A
A
A
B
B
B
A
B
A
30
B
B
A
A
A
B
B
A
A
A
?
ʙᴜᴛᴛᴇʀғʟɪᴇs ᴀʀᴇ ɢᴏᴅ's ᴘʀᴏᴏғ ᴛʜᴀᴛ ᴡᴇ ᴄᴀɴ ʜᴀᴠᴇ ᴀ sᴇᴄᴏɴᴅ ᴄʜᴀɴᴄᴇ ᴀᴛ ʟɪғᴇ
ᴠᴇʀʏ sᴇʟᴇᴄᴛɪᴠᴇʟʏ ᴀᴠᴀɪʟᴀʙʟᴇ ғᴏʀ ɴᴇᴡ ʀᴏʟᴇᴘʟᴀʏs

ᴄʜᴇᴄᴋ ❋ ғᴏʀ ɪᴅᴇᴀs; 'ø' ғᴏʀ ᴏɴs&ᴏғғs, ᴏʀ ᴘᴍ ᴍᴇ.
{ø 𝕨 
  𝕒 }
»  ᴇʟʟɪᴡʀɪᴍᴏ
»  ᴄʜᴏᴏsᴇ ʏᴏᴜʀ ᴏᴡɴ ᴀᴅᴠᴇɴᴛᴜʀᴇ: ᴛʜᴇ ғɪғᴛʜ sᴄʜᴏʟᴀʀʟʏ ᴀʀᴛ
»  ひらひらと舞い散る桜に 手を伸ばすよ
»  ᴘʟᴏᴛ ʙᴜɴɴɪᴇs × sᴛᴏʀʏ sᴇᴇᴅs × ᴄʜᴀʀᴀᴄᴛᴇʀ ɪɴsᴘɪʀᴀᴛɪᴏɴs

Jacqueline

Three riddles for the sphinxes out there!

Reaching stiffly for the sky,
I bare my fingers when it's cold
In warmth I wear an emerald glove
And in between I dress in gold


Two bodies have I
Though both joined in one
The longer I stand still
The faster I run


I run all day but never walk,
I often murmur but never talk,
I have a bed but never sleep,
I have a mouth but never eat,


Enjoy!

The Golden Touch

The first one is a tree.

The second one, I am not sure.

The third one is a river.

"Yesterday was the easy day."
Ideas (Open) /What Floats My Boat\ Absences

Shiny

Heureka!

Colin scored 60 points!

Explanation (Don't look if you want to solve it yourself)


Again, the table for maximum deviation of points.

   
   
   
   
   
NameMaryDanLisaColin
Mary0604030
Dan6002030
Lisa4020030
Colin3030300

Lisa(30) differed by the maximal amount from both Mary(70) and Dan(50). That means, she got question 2,4,5,10 wrong (those where her answers differed from Mary) and question 6,9 (Dan).
The right answers for the first set are those of Mary, for the second set the ones of Dan.



   
   
   
   
   
   
   
Question nr.Right answerColin's answer
2BB
4BA
5AA
6BB
9BA
10BA

This means that Colin scored at least 30 points.
The only questions remaining are nr. 1,3,7,8.
These were answered the same by all students.
Since Lisa scored only 30 points, and she only could have got them from these questions, Colin got 30 points from them as well.

Colin's score is 30 (questions 2,4,5,6,9,10) points + 30 ( questions 1,3,7,8) points = 60 points



Thank you for this excellent puzzle, Caeli!



[/td][/tr][/table]
Nothing great, but for someone to share their thoughts.

warlko

@Caeli

I got the same answer 60 points for Colin.


@Shiny

My problem is not that complex. You are making unmentioned assumptions.

Now in your puzzle all the factors by which a numbered lamp is divisible will be in pairs so that will bring the lamp to its original state except in the square number pair. There are 10 square numbers between 1 and 100 so 10 lamps (1,4,9,16,25,36,49,64,81,100)will remain on.

and in the bonus question we can only infer that the totality of all numbers is infinite, and that the number of squares is infinite so infinite lamps will remain on.


@Elenwe

1- A deciduous tree
2- Hourglass
3- River

Caela

#18
Quote from: warlko on November 11, 2011, 12:07:48 PM
hah! now I've to wait for another thing besides approval..

I've a conundrum...

Four cars are stopped at a four-way intersection. At the same time and at the same speed, they all drive forward and continue their journeys without colliding.
How is this possible?

NOTES:
All the cars are facing forward into the intersection.
The intersection is not large enough for the cars to
cross at the same time and miss each other
(this is possible on larger intersections).
There are no tricks such as overpasses or tunnels.

They're all in a single file line going the same way? (I know this assumes a stop light instead of a stop sign.)

Or they could all be at different four way stops.

Jacqueline

Quote from: warlko on November 11, 2011, 04:50:11 PM

@Elenwe

1- A deciduous tree
2- Hourglass
3- River

Yes, yes and yes, congratulations!

warlko

Quote from: Caela on November 11, 2011, 05:56:22 PM
They're all in a single file line going the same way? (I know this assumes a stop light instead of a stop sign.)

Or they could all be at different four way stops.

No they are not in a single file, they are facing one another and they are at the same intersection


I'll ask another. This one is very simple...

A young man and his father are involved in a terrible car accident. Tragically, the father dies soon after. When the young man arrives at the emergency ward, the surgeon says:
“I cannot operate on this young man … he is my son!”
How can this be so?

Note: the man who died really was the young man’s father!

Oniya

Spoiler: Click to Show/Hide
The surgeon is the young man's mother.
"Language was invented for one reason, boys - to woo women.~*~*~Don't think it's all been done before
And in that endeavor, laziness will not do." ~*~*~*~*~*~*~*~*~*~*~Don't think we're never gonna win this war
Robin Williams-Dead Poets Society ~*~*~*~*~*~*~*~*~*~*~*~*~*~Don't think your world's gonna fall apart
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warlko


Story Tale

This is one of the first my father asked me.


You have a fox, a chicken and a sack of grain. You must cross a river with only one of them at a time. If you leave the fox with the chicken he will eat it; if you leave the chicken with the grain he will eat it. How can you get all three across safely?

Jacqueline

Quote from: najlah on November 17, 2011, 09:02:46 AM
This is one of the first my father asked me.


You have a fox, a chicken and a sack of grain. You must cross a river with only one of them at a time. If you leave the fox with the chicken he will eat it; if you leave the chicken with the grain he will eat it. How can you get all three across safely?

Take the chicken over first. (Poor fox!)
Then go back and bring the grain next.
Instead of leaving the chicken with the grain, come back with the chicken.
Then leave the chicken on the first side and take the fox with you.
Leave the fox on the other side with the grain. (Aw, I can imagine the poor fox looking with sad eyes at the sack of grain again)
And finally go back, get the chicken and bring it over!

It was fun!