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I would like to make the people on this thread aware of the many support groups available for detaching yourself from a calculator, and breaking free into an all-human society. 😉
dr. pepper: I didnt have a number in mind it was completly random.
Is ICOT right?
kapusta: Who uses calculators? I just let someone else use it.
aussie, much better!
dr. pepper, it’s impossibal
what door do you always walk into backwards, very rearly frontwards
a back door? 😉
mroosinsehry-
A car door.
mroosinsehry: Did you write <stong>rearly frontwards on purpose?
kapusta: lol
kapusta, wrong. (i won’t say the anser i’ll wait till someone guesses!!!!!!)
ames: no math wizard here but i think if you make up an equation off the top of your head, it might not work out easily, & you might end up with complicated numbers that are hard to deal with.
no problem
mroos, that was a play on words, you said very rearly
Start with the prime factorization of 1,000,000
= 2 * 2 * 2 * 2 * 2 * 2 * 5 * 5 * 5 * 5 * 5 * 5.
So the two integers must consist of six 2s and six 5s between the two of them.
Any integer that contains a 2 and 5 in it’s prime factorization will end in 0. (2 * 5 = 10 and any integer multiplied by 10 ends in 0.)
=> one integer contains all six 2s and the other one contains all six 5s.
I read this riddle when I didn’t have a calculator nearby (it must have been on shabbos) and the way I calculated (2^6) and (5^6) is by breaking it into squares.
(2^6) = (2^3)^2, we all know that 2^3 = 8 and 8^2 = 64.
(5^6) = (5^3)^2 was a little trickier. 5 * 5 = 25 and 25 * 5 = 125 (5 quarters is 125 cents right?) now 125^2 is what?
Using the trick from the second half of this post http://www.theyeshivaworld.com/coffeeroom/topic/the-riddle-thread/page/8#post-16043
125 * 125 = 100 * ( 12 * 13) + 25 = 15,625.
The two integers are 64 and 15,625 and that is the only solution.
ames-
Did you ever wonder why all college level math text books are written by professors?
Supposedly they make up questions and give them to their students for homework. The ones with solutions are included in the next edition and the ones without solutions are thrown out or edited by the student for extra credit.
When I was teaching high school the software I used to type up exams had an option to check most of the questions to see if there was a solution. (It could only check the computational ones not the word problems and I never used that feature so I don’t know how well it worked.)
The backdoor to a pair of Dr. Dentons?????
ames- I actually heard this from a colleague of mine while I was a teacher and I think he was very serious. Some of the authors list the names of the students who helped review the textbooks.
As far as the software is concerned- I agree that it’s very interesting.
Pretty often when I was creating an exam I started with an answer and went backwards to a question. (For example: X = -3 and 5. Now the question would be “Solve for X: X^2 – 2X = 15.)
The software would ask for ranges for the answers, say from -10 to 10, and design the question accordingly. An advanced option would create a different exam for each student (same questions but different numbers and the correct solutions were randomly placed from A to E for each student). Each test would have a bar code that had to be scanned before the answer sheet was submitted to the Scantron. Of course I couldn’t justify asking the Yeshiva to buy the necessary hardware to combat cheating when it was nonexistent.
I can’t begin to imagine how textbooks were written before PCs. Forget about coming up with problems, just think about the formatting and mathematical notations!
aob you are right , a car door
mroosinsehry: i didn’t have an answer at all. it was icot!
whats “icot”?
mroosinsehry: a different member by the name of “I Can Only Try” (it’s the initials)
see icot’s answer
http://www.theyeshivaworld.com/coffeeroom/topic/the-riddle-thread/page/21#post-67033
(i’ve never linked before nor referenced a specific post so sorry if it doesn’t work.)
oomis1105-
I was thinking along those lines, but decided not to post such an answer.
For the morbidly inclined, “a coffin” would probably be the answer of choice.
an open book-
Thank you.
mroosinsehry-
The young version of an Ibed.
For snack we have Ipeas from an Ipod.
well i’m not sure what happened there with my link, but it does do what it’s supposed to.
icot: no problem. & very cute.
ames- the only hardware missing was the bar code scanner which I can’t imagine was too expensive.
I used a laptop and the yeshiva already had the Scantron sheets and scanner (which could have been hooked up to my computer if I wanted). I would think that they need this more in public schools that prep schools.
Anyone want to take a shot at this again?
In the following equation, what Yom Tov does x equal to: 10^x = baomer?
(It was taken from the secular riddle 10^x = cabin.)
Log Baomer = 33
Isn’t that also the integral of 1/baomer dbaomer? Although that would be ln baomer, I guess. Your way is unnatural.
ulisis: i would like to welcome you back to the cr, seems like you were away long from your profile!
ulisis-
The integral of (1/baomer) dbaomer would be ln |baomer|, (don’t forget those absolute value signs, unless you specify that baomer is strictly positive).
However the integral of 1/(ln(10)*baomer) dbaomer would in fact be Log(BaOmer) since Log (base 10) BaOmer = Ln (Baomer) / LN (10), and stam Logs (no specified base) are base 10.
=> Log (base 10) BaOmer = Log(BaOmer)
Don’t forget
+ C !
That’s right, don’t forget the Constant.
Here’s a riddle that someone just sent me, that I liked. Note to Dr. Pepper – please don’t figure it out right away!
You are sitting at a table with 100 pennies on it. You are blindfolded, and told that 90 of the pennies show heads, and the other 10 show tails. You have to split the pennies into two piles, such that the two piles each have the same number of tails. It does not matter if the two piles have the same number of pennies; it only matters that the number of tails must be the same. Assume that you cannot distinguish between heads and tails by touching and feeling the coins (e.g. they are paper cut-out pennies from a kid’s play money). How do you do this?
Can you turn any of them over?
What if you put them into two piles of 50, with all the coins on their side, like in a roll?
Did I answer correctly or was that a cheat?
Dr. P, I don’t see why not. But you shouldn’t be working on this in the first 15 minutes after I posted. I give you a 3 hour handicap, to give someone else the chance.
JayMatt, creative, but cheating. So is taking them off the table. So is rubbing off the heads and tails.
squeak-
This sounds like a symantic misdirection riddle.
If you put fifty in each pile, each will have the same number of tails (you said have not show.
squeak-
Never mind – I was wrong.
I lost patience and googled the answer.
Great riddle!
hey so did i (thanks for the idea)
really cool one, squeak
Wow! There are so many loopholes to close with this riddle! For the record, I meant that the two piles need to SHOW the same number of tails.
Can you let me know when I can give a shot at it?
I’m waiting very patiently.
Thanks
(Is it just me or is the formatting messed up in this thread?)
I said 3 hours, and it’s been less than 2. I’m just kidding, really. I know that you would probably get the right answer in <2 minutes, so I wanted you to give other people a chance to see the riddle without seeing the answer. But if your engines are revving, go ahead. 😉
BTW, the formatting on this page is messed up since 2 weeks ago. See ICOT’s post above. If a mod would go back and close the expression, all would be back to normal. This happens from time to time.
Make two piles. One has 90 pennies the other one has 10.
The 90 penny pile has X tails while the 10 penny pile has 10-X tails (and therefore X heads).
Turn over all the pennies in the 10 penny pile and now that pile has 10-X heads and X tails.
Now both piles have X tails. (Although X can be any integer between 0 and 10 inclusive.)
My editor pointed out:
Semantic is the word I meant to use.
Symantec is the anti-virus software company.
ICOT – thanks for pointing that out – its now fixed. Let me know if there is still a problem.
YW Moderator-25-
You’re welcome.
It’s an issue for Internet Explorer – Firefox displays fine (I don’t have Google Chrome, so I don’t know how it displays there).
It looks fine now on IE.
OK great, thanks! –YW Moderator-25
Is it even necessary for me to say that Dr Pepper has once again given the correct solution.
i missed this one 🙁 (he really should have that handicap) do you have another one?
for all you gemorah kups out there (and if your not a gemorah kup you can try anyway)
2 people come down a chimney 1 clean the other dirty.
who washes their face?
Santa
~a~
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