If you're going to be 2 boxing, please change prophylactics before switchin
Re: Maths
Posted: Wed May 12, 2021 3:36 am
by Crunchums
pfffffff
Re: Maths
Posted: Thu Jan 06, 2022 3:22 pm
by Doug
I thought this was a cool problem but maybe it's dumb. I'm paraphrasing
Fred tells Lucas, I'm thinking of two different one-digit whole numbers. Can you tell me their sum
Lucas says, the sum of the numbers you happen to be thinking of? Of course not
Fred says, ah but what if I told you that when we multiply the two numbers, the last digit of the product is the same as the number you played on the roulette wheel a moment ago, now can you tell me their sum
Lucas says, well actually yes
What is their sum
Re: Maths
Posted: Thu Jan 06, 2022 4:04 pm
by Crunchums
Spoiler!
0 -> lots of ways to get here obv
1 -> 3 and 7 only
everything greater than 1 will have X and 1 so any other pairing with a different sum makes it impossible for it to be that one
2 -> 2 and 6
3 -> 9 and 7
4 -> 7 and 2
5 -> 5 and 3
6 -> 3 and 2
7 -> 3 and 9
8 -> 2 and 4
9 -> 9 and 1 only
so 10
Re: Maths
Posted: Thu Jan 06, 2022 4:43 pm
by Khaos
Spoiler!
if the number is 36, the factors are 1, 2, 3, 4, 6, 9, 12, 18, and 36.
we can eliminate 12, 18, and 36 since they are two digit numbers. and thus eliminate 1, 2, and 3. we can eliminate 6, because the number can't be duplicated. so the answer is 4 + 9 = 13. but that's one case. i don't wanna do all the cases. but 36 is the most highly composite number within the provided range so it's probably the worst case
BUT! i looked at a table of factors and it looks like it fails for the following roulette numbers:
24
18
12
8
6
weird
Re: Maths
Posted: Thu Jan 06, 2022 4:44 pm
by Khaos
oh the last digit of their sum. woops
Re: Maths
Posted: Thu Jan 06, 2022 4:48 pm
by Doug
Khaos wrote: ↑Thu Jan 06, 2022 4:44 pm
oh the last digit of their sum. woops
no the last digit of their product
Re: Maths
Posted: Thu Jan 06, 2022 5:11 pm
by Khaos
Doug wrote:
Khaos wrote: ↑Thu Jan 06, 2022 4:44 pm
oh the last digit of their sum. woops
no the last digit of their product
right. that's what i meant. anyway the important part is that i did it wrong
Re: Maths
Posted: Fri Jan 07, 2022 3:12 am
by groff_enthusiast
Totally a barenstein effect here, but I could have sworn there were two different "pairs" with an identical sum but different product. I got the same answer as crunchums
Edit: I both can't read and can't think, yeah that's exactly what this is.
Re: Maths
Posted: Thu Aug 04, 2022 5:43 am
by Luna
Re: Maths
Posted: Thu Aug 04, 2022 5:47 am
by Ashenai
that is a good looking riemann surface
Re: Maths
Posted: Thu Aug 04, 2022 2:22 pm
by Jeb Bush 2012
thank you arti
Re: Maths
Posted: Thu Aug 04, 2022 2:43 pm
by Khaos
you've done a wonderful job
Re: Maths
Posted: Thu Aug 04, 2022 3:01 pm
by Doug
Time Cube except nothing but positivity
Re: Maths
Posted: Thu Apr 20, 2023 8:40 pm
by Doug
You guys are math people so you probably find this easy and dumb. I find it fascinating, though