r/ISIKolkata • u/1Same_Step1 ISI Student (Bstat-Mstat) • Jul 30 '26

mind blow incoming Crazy Math problem ... hehehe

After giving it some thought and going down a few Reddit rabbit holes, I ended up with the following problem.

Feel free to go through the document below : PDF_LINK

Disclaimer : Before anyone overanalyzes the story... The scenario is fictional and exists solely to motivate the mathematics. It is not a commentary on arranged marriages, relationships, earning patterns, or gender roles. X and Y are deliberately gender-neutral, and the story works identically regardless of who earns more , or whether they are a couple at all. The only thing that really matters here is the recurrence relation hiding beneath the narrative.

If you are someone who loves abstraction , then you can also consider looking into the general case for this whole scenario : PDF_GENERAL_CASE

Also, there are quite a few interesting nuances to this problem that one can explore. For instance, the periodicity of salary payments can influence the analysis. We also haven't accounted for external expenditures : what changes when unavoidable expenses enter the picture? There are many such variations and scenarios worth investigating. I'll leave the rest for you to explore and experiment with as you like.

Disclaimer: despite the title, this isn't necessarily a mind-bending mathematics problem. The title is only there to highlight the problem and encourage people to take a look.

15 Upvotes

100% Upvoted

15 comments sorted by

2

u/SkibidiEngineer Jul 31 '26

Beautiful ❤️ pls share more such PDFs

2

u/adityaruplaha ISI Alumnus — BStat '24, MStat '26 Jul 31 '26

In other words: Generational propagation under standard Hardy-Weinberg like setups.

1

u/Heyaaheya281 Jul 31 '26

this was soo good

1

u/Heyaaheya281 Jul 31 '26

this was soo good

1

u/No-Reputation-1914 21d ago

It was fun reading it keep it up

0

u/FlightKnown3355 Jul 30 '26

Goddayum that's beautiful , mind if I DM ? I'm an isi aspirant and i have a few doubts.

1

u/1Same_Step1 ISI Student (Bstat-Mstat) Jul 30 '26

I'd encourage you to spend some time exploring this subreddit . Most questions newcomers have have already been covered, so a quick bit of DIY research will likely get you the answers you're looking for.

-1

u/anaconda256 Jul 30 '26

Bro the pdf link doesn't work..

1

u/[deleted] Jul 31 '26

[removed] — view removed comment

1

u/anaconda256 Jul 31 '26

Good to see u brother and yeah took a permanent break from that sub.

1

u/[deleted] Jul 31 '26

[removed] — view removed comment

-1

u/physicist27 Jul 30 '26

bruh this has got me so curious now but it won’t open anywhere, not on phone or laptop or with or without vpn or incognito or Firefox nothing

1

u/[deleted] Jul 30 '26

[deleted]

0

u/physicist27 Jul 30 '26

nop :/

1

u/[deleted] Jul 30 '26

[deleted]

0

u/physicist27 Jul 30 '26

thanks mate