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RE: Ask a Mathematician
December 10, 2021 at 9:59 pm
(December 10, 2021 at 8:12 pm)brewer Wrote: What's the deal with 3, 6, and 9? (I think it's just about 3 but.........)
3x4=12, 1+2=3
6x24=144, 1+4+4=9
9x2025=18225, 1+8+2+2+5=18, 1+8=9
6x85069=510414, 5+1+0+4+1+4=15, 1+5=6
3x50647921=151943763, 1+5+1+9+4+3+7+6+3=39, 3+9=12, 1+2=3
Nonfunctional math guy is curious.
I'll let polymath257 do the honors for modulo arithmetic.
If you get to thinking you’re a person of some influence, try ordering somebody else’s dog around.
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RE: Ask a Mathematician
December 11, 2021 at 2:05 pm
(December 10, 2021 at 8:12 pm)brewer Wrote: What's the deal with 3, 6, and 9? (I think it's just about 3 but.........)
3x4=12, 1+2=3
6x24=144, 1+4+4=9
9x2025=18225, 1+8+2+2+5=18, 1+8=9
6x85069=510414, 5+1+0+4+1+4=15, 1+5=6
3x50647921=151943763, 1+5+1+9+4+3+7+6+3=39, 3+9=12, 1+2=3
Nonfunctional math guy is curious.
It boils down to the fact that if you divide 10 (the base of our number system) by 3 or 9, the remainder is 1. because of that, when you divide 100 or 10000 or any power of 10 by 3 or 9, the remainder will be 1.
This is actually the basis of a lot of strange arithmetic tidbits.
The effect is that when you divide a number by 3 or 9, the remainder will be the same as what you get if you divide the sum of the digits by 3 or 9. You can keep doing this until you have a single digit number.
So, if you start out with a multiple of 3, the final, single digit has to be 3, 6, or 9.
If you start out with a multiple of 9, the single digit has to be 9.
Here is a variant, that is due to the fact that 10 is the same as -1 when you divide by 11.
Take any multiple of 11 and alternately add and subtract its digits. Than do the same with the answer. Eventually, you will get to 0.
Example:
11x5971=65681. 6-5+6-8+8-1=11, 1-1=0.
11x821074=9031814, 9-0+3-1+8-1+4=22, 2-2=0
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RE: Ask a Mathematician
December 11, 2021 at 2:15 pm
Math lobe hurts now.
I don't have an anger problem, I have an idiot problem
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RE: Ask a Mathematician
December 11, 2021 at 2:17 pm
I math every day as a bookkeeper but Algebra and beyond are beyond what my brain can process.
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RE: Ask a Mathematician
December 15, 2021 at 11:55 pm
Most people do basic algebra every day and are blissfully unaware of it. I had a friend who swore she couldn't do it until I asked her what she thought she was doing every time she did a cost estimate for a client based on the dimensions of the project. I wouldn't want to write out formally what she was doing in her head.
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RE: Ask a Mathematician
December 16, 2021 at 7:47 am
(December 15, 2021 at 11:55 pm)Paleophyte Wrote: Most people do basic algebra every day and are blissfully unaware of it. I had a friend who swore she couldn't do it until I asked her what she thought she was doing every time she did a cost estimate for a client based on the dimensions of the project. I wouldn't want to write out formally what she was doing in her head.
Algebra is just arithmetic with letters.
And without delay Peter went quickly out of the synagogue (assembly) and went unto the house of Marcellus, where Simon lodged: and much people followed him...And Peter turned unto the people that followed him and said: Ye shall now see a great and marvellous wonder. And Peter seeing a great dog bound with a strong chain, went to him and loosed him, and when he was loosed the dog received a man's voice and said unto Peter: What dost thou bid me to do, thou servant of the unspeakable and living God? Peter said unto him: Go in and say unto Simon in the midst of his company: Peter saith unto thee, Come forth abroad, for thy sake am I come to Rome, thou wicked one and deceiver of simple souls. And immediately the dog ran and entered in, and rushed into the midst of them that were with Simon, and lifted up his forefeet and in a loud voice said: Thou Simon, Peter the servant of Christ who standeth at the door saith unto thee: Come forth abroad, for thy sake am I come to Rome, thou most wicked one and deceiver of simple souls. And when Simon heard it, and beheld the incredible sight, he lost the words wherewith he was deceiving them that stood by, and all of them were amazed. (The Acts of Peter, 9)
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RE: Ask a Mathematician
January 2, 2022 at 12:45 pm
What has been your greatest personal challenge in this field? And greatest personal achievement.
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RE: Ask a Mathematician
January 2, 2022 at 12:55 pm
At work.
(December 8, 2021 at 10:27 pm)polymath257 Wrote: I've been a research mathematician for the last 35 years. Any questions?
During your research havd found out if putting racing stripes on the numbers helps counting them go faster?
Have you tried painting them red?
XD
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RE: Ask a Mathematician
January 2, 2022 at 3:15 pm
(January 2, 2022 at 12:45 pm)GrandizerII Wrote: What has been your greatest personal challenge in this field? And greatest personal achievement.
Biggest personal challenge: that I am not as intelligent and creative as I would like to be.
Greatest personal achievement: applying algebraic topology to a question in measure theory. The two subjects are quite far apart and to find a connection was quite a trip.
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RE: Ask a Mathematician
January 2, 2022 at 7:43 pm
(January 2, 2022 at 3:15 pm)polymath257 Wrote: (January 2, 2022 at 12:45 pm)GrandizerII Wrote: What has been your greatest personal challenge in this field? And greatest personal achievement.
Biggest personal challenge: that I am not as intelligent and creative as I would like to be.
Greatest personal achievement: applying algebraic topology to a question in measure theory. The two subjects are quite far apart and to find a connection was quite a trip.
As an undergraduate, I had a love (and still do) of mathematics & physics, and had contemplated going to graduate school, but, (somewhat) sadly was forced to conclude that my principle (and, likely, only) accomplishment as a graduate student would have been to have made the top half of my graduating class possible.
And, so, after graduating, I went into industry and bought a car, a Z24.
And without delay Peter went quickly out of the synagogue (assembly) and went unto the house of Marcellus, where Simon lodged: and much people followed him...And Peter turned unto the people that followed him and said: Ye shall now see a great and marvellous wonder. And Peter seeing a great dog bound with a strong chain, went to him and loosed him, and when he was loosed the dog received a man's voice and said unto Peter: What dost thou bid me to do, thou servant of the unspeakable and living God? Peter said unto him: Go in and say unto Simon in the midst of his company: Peter saith unto thee, Come forth abroad, for thy sake am I come to Rome, thou wicked one and deceiver of simple souls. And immediately the dog ran and entered in, and rushed into the midst of them that were with Simon, and lifted up his forefeet and in a loud voice said: Thou Simon, Peter the servant of Christ who standeth at the door saith unto thee: Come forth abroad, for thy sake am I come to Rome, thou most wicked one and deceiver of simple souls. And when Simon heard it, and beheld the incredible sight, he lost the words wherewith he was deceiving them that stood by, and all of them were amazed. (The Acts of Peter, 9)
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