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I’ll take the photo – but it better include the mishpacha.
Dr. Pepper-
squeak-
I would be impressed, except at this point I figure the only way the Dr. doesn’t come up with the answer instantly is if he’s giving others a chance.
I feel like a five-year-old who shows off that he knows the alef-bais by heart, only to hear a rosh yeshiva follow it with a two-hour pilpul.
Dr. Pepper – don’t be modest now, because I’m really curious – is this level of math expertise common among math majors? Among holders of a math PhD?
squeak
This brings back memories from when I first solved this problem on my abacus… If you read post # 203 http://www.theyeshivaworld.com/coffeeroom/topic/the-riddle-thread/page/6#post-12885 in this thread you’ll understand how I remember the question.
Anyway- what’s “clam stuff”?
And by the way- I am not that old, I was born after the 50s.
Here’s somewhat of a riddle for the engineers following the thread.
Why are the towers of the Verrazano-Narrows Bridge 1.625 inches further apart from each other at the tops than at the bases? (Both towers stand perfectly plumb.)
Dr. Pepper-
The curvature of the earth (3d geometry).
I remember reading thet the German Big Bertha cannon of WWI had to include that factor in their trajectory calculations since it fired a projectile 75 miles.
If I understand your reference, Dr P, you are telling me that you copy and pasted the solution from elsewhere, right? 😉
The clam stuff was a joke since Motts is owned by your company and was making problems for the kosher consuming community with its clam derivitive product.
BTW, I was also born after 1850.
squeak
brute force method using Excel: (only copy and paste what is between the quotation marks)
Cell A1 “1”, Cell B1 “=((((((A1)*5/4+1)*5/4+1)*5/4+1)*5/4+1)*5/4+1)”, Cell C1 “=B1-INT(B1)”
Select Cells A1 – A3 and move the cursor to the bottom right hand corner of Cell C1 until it turns into a + sign. Now click on the + sign and drag the formulas down a few thousand rows.
Select column “C” and on the “Standard” toolbar click “Sort Ascending” (The icon has an A on top of a Z with a down arrow on the right side). Select to “Expand the Selection” and click “Sort”. The rows where the entry in column C is 0 are possible solutions.
Solution to post # 292 http://www.theyeshivaworld.com/coffeeroom/topic/the-riddle-thread/page/8#post-15915
In the following equation, what Yom Tov does x equal to: 10^x = baomer?
Take logs of both sides Log(10^x) = x = Log(baomer)
Dr. Pepper: How do you know which post is what post #?
squeak demands riddles, so here they come…
A man walks into a bar in, sets down two identical US bills on the counter, and makes an order. He asks for one rum, two margaritas, one vodka, two Pepsis, one lemonade, and three waters.
The bartender, who always gives change back in the minimum number of coins and bills possible, gives him two bills and one coin in change, then goes to prepare his drinks.
The man realizes that if he had paid the bartender with only one of any larger bill, he would not have received the same change. When the bartender returns, the man takes his drinks and leaves the bar.
The man returns home and decides to challenge his wife. He tells her what he ordered, how much it cost, and how much change he received. Then he gives her the following seven clues:
1. For every one of a specific drink bought, a customer can buy another of the same drink for half price. (When necessary, the tab is rounded up to the nearest penny after all drinks have been ordered.)
2. If a customer buys five vodkas or one of any other drink, the bartender does not have to give any coins with the change
3. If he had bought one lemonade, one margarita, or one lemonade and two margaritas with the amount he paid for his order, the bartender would have given him back no fewer than six bills
4. If he had added a second rum to his order, the total number of bills plus the total number of coins the bartender would have given him back would be no fewer than six
5. The second of any alcoholic drink never costs less than any non-alcoholic drink
6. No drink costs more than the first margarita
7. Three waters cost less than the first of any other drink
Finally, he asks his wife how much each drink cost him.
How much does each drink cost, and which clue does the wife not need to determine the cost of each drink?
Assume that margaritas, vodkas, and rums are the only alcoholic drinks; $1, $5, $10, $20, $50, and $100 bills are the only US bills; and 1, 5, 10, and 25 cent coins are the only US coins.
What English word is nine letters long, and can remain an English word at each step as you remove one letter at a time, right down to a single letter. List the letter you remove each time and the words that result at each step.
squeak-
“BTW, I was also born after 1850”
– C.E. or Hebrew calendar?
<<couldn’t resist – no offense, I’m in the same boat>>
Joseph-
Hover over the hash-mark to the right of the timestamp. A tooltip with the post# will appear.
ICOT – none taken. You can’t flaunt your age and then be offended by jokes about it.
And the answer is: Both, C.E. and Hebrew Calendar.
I can only try-
“Dr. Pepper – don’t be modest now, because I’m really curious – is this level of math expertise common among math majors? Among holders of a math PhD?”
I hate questions like this because I don’t want to appear arrogant. The math used to solve that riddle was basic algebra and arithmetic (the MOD(x,y) function is just a fancy way of getting the remainder of x divided by y).
Let me try to explain the thought process of a mathematician the way I heard it from the son of a math professor (it’s not supposed to be funny so don’t complain that you find it corny):
Q. What do you do if you see a piece of wood on fire and a pail of water next to it?
A. Use the pail of water to put out the fire.
Q. What do you do if you see a piece of wood on fire and there is no pail of water next to it?
A. Go get a pail of water and put out the fire.
Q. What do you do if you have a pail of water?
A. Go find a piece of wood to set on fire so you can pour the bucket of water on it.
The way a mathematician goes about solving a problem is to take it apart and change it around to fit into an equation he knows how to handle.
By the time a math major gets to upper level math courses, even calculus should come naturally. When they are trying to set up a mathematical model to solve some sort of equation on an exam they don’t have time to try to figure out how to differentiate or integrate the equation.
Joseph,
“Dr. Pepper: How do you know which post is what post #?”
Easy- find the post, count how many down on the page the post is, multiply the page number by 40 and add the two together.
Dr. Pepper –
Can you reduce the riddle I presented on top of this page (the long one) into a mathematical equation?
I think explaining your expertise is not arrogance. Rather, it helps laymen understand the value of your expertise. Imagine if you ask the plumber working on your pipes “How do you do that so well” and he says “It’s really easy, anyone could do it” because he doesn’t want to brag about all the training and experience he has under his belt.
Comes time to pay the bill, you’ll be wondering why he gets $1200 for something so easy.
Dr Pepper –
Not very intuitive 🙂
Besides, the # of posts per page has changed 3 times already – from 20 to 30 to 40 – and once in a while a post may be deleted renumbering everything else.
ICOT –
I’m not getting that tooltip for some reason.
A train track runs between 2 train stations.
It takes exactly 12 hours for a train to go from station A to station B and the same amount of time from B to A.
Every hour, a train leaves from each station.
If you get on a train at station A, how many trains will you pass coming in the opposite direction from station B?
Dr. Pepper-
Joseph-
The URL info appears in the info area on the bottom left of my browser (IE) when the cursor hovers over the hash mark.
Joseph-
Margarita: 6 x 1.5 = 9
Vodka: 5.75 x 1 = 5.75
Rum: 5 x 1 = 5
Pepsi: 2 x 1.5 = 3
Lemonade: 2 x 1 = 2
Water: 0 x 3 = 0
2) the only number that give six or more bills in change from $40 are 1,2,6,11 and 21. if margarita$ = a and lemonade$=b and a / 2 >= b (cond. 5) a can only be 1 or 2, b can only be 6 or 11. since a x 1.5 + b must be 11 or 21, the only combo that works is a (margarita) = 6, b (lemonade) = 2
3) water <= lemonade x 3. since only vodka has a non-integer price, water = 0.
4) The coin in change can only be a quarter (the whole dollar amounts of drinks can only be divided by 2, and vodka x 4 = an integer).
5) The total is over $20 (11 margarita and lemonade, at least 4 for the rum, at least 4.25 for the vodka an at least 1 for the pepsi). This means the change can either be 2.25, 6.25, 11.25 or 15.25 (two bills, one quarter).
7) Rum is 4,5 or 6 (floor = 2 x lemonade, ceiling = margarita). A second rum returns >= (six coins + bills) change. This only works if the second rum is 2.50. Rum = 5.
I used all the clues, so I don’t know which is extra.
ICOT,
My answer is somewhat different than yours. I’m away from my place now, but will get back. I believe there is more than one possible answer.
Accessory to a Crime?
Yankel, an average bal habos, living in Detroit, had an interesting morning.
He got up, davened, and had his usual mug of Sanka with a Danish for breakfast.
While walking from his porch to his eight-year-old GM minivan, he saw a murder on his front lawn.
Instead of calling the police, he calmly drove to work.
During his commute, he saw a large business that he knew had changed hands due to Ransom being paid, but again he just continued on his way.
When he got to his desk, his secretary asked him how his morning had been so far.
How could Yankel have been so casual about what he had seen?
Had he become a lawbreaker?
Indifferent to crime?
moderator – please replace my earlier “cleaned up” version with this one. the data i put in the earlier post inadvertantly contained HTML tags, which is messing up the page and making my posting unreadable. sorry!
2) The only numbers that give six or more bills in change from $40 are $1, $2, $6, $11 and $21. If margarita $ = x and lemonade $ = y and x / 2 >= y (cond. 5), x can only be $6 or $11, y can only be $1 or $2. Since x * 1.5 + y must be $11 or $21, the only combo that works is x(margarita) = $6, y(lemonade) = $2
3) Water * 3 <= lemonade. Since only vodka has a non-integer price, water = $0.
4) The coin in change can only be a quarter (the whole dollar amounts of drinks can only be divided by 2, and vodka * 4 = an integer).
5) The total is over $20 ($11 margarita and lemonade, at least $4 for the rum, at least $4.25 for the vodka an at least $1 for the Pepsi). This means the change can either be $2.25, $6.25, $11.25 or $15.25 (two bills, one quarter).
7) Rum is $4.50 or $6 (floor = 2 * lemonade, ceiling = margarita). A second rum returns >= (six coins + bills) change. This only works if the second rum is $2.50. Rum = $5.
ICOT:
Ya got it! Congrats, how long did it take you? 🙂
(and it is the only answer.)
Btw, the result works without Clue 3.
ICOT- i am guessing that the “murder” that took place on Yankel’s front lawn was a cat killing a bird or a squarrel, which is “nothing special.”
i cant figure out the ransom part, though. Did he drive by Ford and see that they were ransomed,er,bailed out by the gov.?:)
seriously, please post the answer. i abhorr math but i love word games.
Joseph-
Thank you.
My best guesstimate is about 2 – 2.5 hours, starting last night and resuming during lunch today.
I used clue #3 in my seventh step, so there is probably a more elegant solution that I missed.
Step 1 was easy, 2 was not too difficult, and 3 fell into place following two.
Steps 3, 5, 6, and 7 were challenging.
Step 8 fell into place once the others were done.
That was an enjoyable puzzle.
Your nine letter word is:
startling
starling
staring
string
sting
sing
sin
in
I
This was in a kid’s magazine I read about 35 years ago (I don’t remember the name, but it had a comic about a detective with a dog called Tin-Tin and two bumbling policement called the Thompson Twins).
I am “chapping” it because no one else got it, and after 24 hours my “no chap” moratorium is up.
chasid-of-Hashem-
If you get the answers right away kol hakavod, but otherwise let’s let others try to solve it.
Here are a couple of hints in the meantime:
a) Who said anything about a killing?
b) In the sentence beginning with the word “During”, there are no misspellings or typos.
ICOT
1)a murder is a flock of crows. and 2)you said “due to Ransom” – skipping the word “a” and capitalizing the “r” so i’m assuming “Ransom” is the name of a person who bought the business.
thanks for the tips!
ICOT:
Indeed correct regarding the nine letter word.
2.5 hours of your valuable time over two days… what is your consultancy rate on tough riddles?
brooklyn19-
Correct!
Ransom Eli Olds was the person Oldsmobile is named after, and he is the one who sold the business (he was actually bought out, but it’s a long story), hence Ransom was paid.
I threw a couple of clues into the original puzzle:
a) Yankel drove an eight-year-old GM minivan (GM discontinued the Olds brand a few years back).
b) Yankel lived in Detroit.
After Olds was bought out, he started another auto company named “REO” – his initials. It failed.
Joseph-
“what is your consultancy rate on tough riddles”
– One Jolt cola, or two asprin – whichever kicks in faster.
Alternately, potato kugel.
ICOT
just don’t take the cola WITH the asprin…
Next Riddle:
What is the meaning of life?
Two Cryptogram Puzzles
Cryptogram Puzzle # 1
Let’s start with a simple Caesar cipher. If you have worked on cryptograms before, you’ll want to skip past this one, as it will not be much of a challenge.
Decipher the following quote from a famous mathematician:
fq pqv yqtta cdqsv aqwt fkhhkewnvkgu kp ocvjgocvkeu. k ecp cuuwtg aqw okpg atg uvknn itgcvgt. – cndgtv gkpuvgkp
Cryptogram Puzzle # 2
This one uses numbers in place of letters.
Decipher the following quote about intelligence.
3325863186 2432 881621163412 3216 24313124331933248826 1932 3216878621163412 53243325 89863232 248833868989242686884286 198834 87163186 3286883286 33251988 5386 25195786. – 341688 258631168934
As you might imagine, a cipher using numbers can be tougher than one using letters. There are only 26 letters in English after all, while even just using a two-digit number for each letter allows for 100 possible substitutions.
This isn’t a very difficult cryptogram, however. It still uses a simple alphanumeric-substitution cipher, and so can be solved using letter-frequency analysis or even a brute force attack, in which you try out the various possibilities one after the other.
For the logical amongst us… 2 logic riddles:
Riddle #1: The Problem Of The Brainwave CD Weights
You manufacture brain wave entrainment CDs for companies that sell self-improvement products. You are at the post office, with ten boxes of them ready to close up and ship out, but you have a problem. Nine of the boxes contain CDs that are designed to put the listener into an “alpha” or relaxing state, and one is full of Cds that are designed to put the user into a deeper “delta” state, for deep sleep. They look identical, and you forgot to label them.
There is one difference, however. You remember that the “alpha” Cds weigh 13 grams, and because different CD “blanks were used, the “delta” Cds weigh 15 grams. Unfortunately, you can’t feel the difference in weight by lifting them.
The post office does have a scale. It costs one dollar each time you weigh something, though, and you want to keep your costs down. How do you use the scale as few times as possible to determine which are the “delta” CDs?
_____________________________________________
Riddle #2: Weighing The Gold
You have 15 tiny gold bars and a balance scale. One of the bars is lighter than the others, but you can’t tell the difference by feel. What is least number of times you could use the scale to determine which one is the light one?
Joseph,
You wrote: “What is the meaning of life?”
That’s easy. 42.
anon, are you answering a riddle with a riddle?
No, it’s a reference to _The Hitchhiker’s Guide to the Galaxy, a book by Douglas Adams, in which a supercomputer is built to discover the answer to “Life, the Universe and Everything”. It comes up with 42 as the answer.
Sorry for being flip. But your question was such a perfect setup that I couldn’t resist.
anon: If you or anyone does come up with the actual answer to “What is the meaning of life?”, I’d assume we’ll all hear about it as your accepting your prize in Oslo…
Until then can anyone address one of the more simpler riddles here, either one of the two Cryptogram Puzzles or Logic Riddles presented.
🙂
joseph, for riddle #1:
i would split them into two groups of five and weigh one. if it equals to 67 grams, you know the delta ones are in that pile and you split that group into 2 and 3, weighing one of them.
if the original 5 only weighs 65 grams, you know they are all alphas and you go directly to step 2 of the first group (weighing 2 or three of them)
am i right? (this is so not my thing!)
brooklyn19, that would work, but would require using the post office scale more than the optimal method. He wans to keep his costs down, and use the scale the least possible number of times.
42 makes sense. But only because I understand the question.
intellegent-
I think the answer to your “train” riddle is 25:
One on the hour * 13 + one on the half-hour * 12
Joseph-
Cryptograms are logic puzzles, but they take a while, so I’m skipping them for now.
Your “brain wave cd” puzzle was asked by Feivel on the first page of this thread, in a different format (if there are multiple CDs per box). If there is only one CD per box, you need three or four tries, depending on how lucky you are.
The “15 gold pieces” solution is three. Split the pieces into three groups of five (lets call them x, y and z), and compare x vs. y.
Split the group thay is lightest into three groups of two, two and one (lets call them za, zb and zc).
Compare za vs. zb.
If they are equal, zc is the exception, otherwise split the group with the exception and perform one more compare.
Gut voch.
I can only try –
re: the “brain wave cd” puzzle, if your referring to Feivel’s coin puzzle on page 1, this is different (and not the answer your gave in your last response.) And the response requires no luck.
re: the “15 gold pieces”, your answer is correct; I have another solution though:
1. Put 7 gold bars on each side. If they are equal in weight, the one left out is the light one. If unequal, go to step two.
2. Take the gold bars from the lighter side and put three on each side. If they are equal in weight, the one left out is the light one. If unequal, go to step three.
3. Take the gold bars from the lighter side and put one on each side. One will be the light one, or if they are equal in weight, the one left out is the light one.
The Incredible Shrinking Watermelons.
Chaim the farmer brought his produce to market one hot summer day.
Unfortunately, he left a box containing 100 lbs. of watermelon behind in the hot sun.
As you know, watermelon is made up mostly of water.
When Chaim left in the morning, the watermelons were 99% water, 1% solid.
By the time he returned they were 98% water, 2% solid.
The question: how much do the watermelons now weigh?
50 pounds.
The weight of the solids is 1 percent — which was 1 pound when the watermelon weighed 100 pounds. That same 1 pound is now the 2 percent of the watermelon after the water evaporation. So figure out 2 percent of what weight is 1 pound. 0.02x = 1 lb., x = new weight (50 lbs.)
joseph-
life is a delicious breakfast cereal. Does any one know the meaning of cinnamon life?
(sorry for being so corny)
Can you punctuate the following, in order to make it a proper English sentence?
I said that that that that that man wrote should have been underlined
You can take away the whole and still have some left. You can take away some and still have the whole left. What is it?
The thunder comes before the lightning; the lightning comes before the clouds. The rain dries everything it touches.
What are the only English words with three consecutive repeated letters. For example, sweet-toothed would be one (ee,tt,oo) if it weren’t for the hyphen.
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