[Request] how practical is buying the USA?
https://redd.it/1qkfexu
@TheyDidTheMath
[Meta] Americans will use anything but the metric system: Winter Storm edition
https://redd.it/1qkcu43
@TheyDidTheMath
Request Could you build a house using TVs cheaper than a normal house?
OK. I'm going to cheat a bit on "house" on this one. But could you make a shell of a house cheaper using Black Friday deal TVs than you could build a similar square footage house?
No money is spent connecting the TVs to each other. We are shooting for a 1900 sq-ft house. TVs will be all walls and roof (shell only no interior walls).
What's the price per square foot as compared to just buying a house in different cities?
https://redd.it/1qk89ok
@TheyDidTheMath
Request Using Shannon entropy to measure portfolio diversity - is this the right approach?
I've been exploring cross-domain applications of information theory and wanted to share an interesting calculation: using Shannon entropy to quantify portfolio diversity.
The Mathematical Setup:
Given portfolio weights w = [w₁, w₂, ..., wₙ\] where Σwᵢ = 1:
H(w) = -Σ(wᵢ × log₂(wᵢ))
Normalized: H_norm = H(w) / log₂(n) × 100
Example Calculations:
\- Portfolio A: [0.60, 0.30, 0.10\] → H = 1.30 → Score: 82/100
\- Portfolio B: [0.33, 0.33, 0.34\] → H = 1.58 → Score: 100/100
\- Portfolio C: [0.85, 0.10, 0.05\] → H = 0.74 → Score: 47/100
Portfolio A has more concentration risk despite having the same number of positions as Portfolio B.
Questions:
1. Is Shannon entropy the right metric for measuring non-uniform distribution? Or would KL divergence from uniform be better?
2. Should weights be correlation-adjusted? (e.g., two highly correlated positions = less actual diversity)
3. For the Taylor series approximation of ln(x), is 20 iterations sufficient for accuracy?
I built a tool that does these calculations: https://3bvys-4aaaa-aaaap-qrfua-cai.icp0.io/
Is this mathematically sound? What would you improve?
https://redd.it/1qk5xuc
@TheyDidTheMath
[Request] Need help figuring out if below couch with fit through a 29.5 inch wide doorway
https://redd.it/1qk0rt5
@TheyDidTheMath
[Request] What latitude range is this method for? If I flip my hand, with my pinkie (the thinnest) on top, would it be more accurate?
https://redd.it/1qk0x53
@TheyDidTheMath
Request Pollution calculation for Bergen Engines B36:45V compared to my municipality power generation.
Recently, my town has approved the creation of New Jersey's largest data center. The data center will be run on 36 B36:45V 11.2 MW generators presumably running on natural gas. I want to compare the total emissions of our local power generation center (I've attached the most recent permit) and the data sheet from Bergen Engines. Is my math correct?
Bergen Engines states 63,500 kg/h exhaust mass but it doesn't have a breakdown of what the exhaust gasses are.
My local 68 MW power generation station produces 313,392.194 Tons/Year of a variety of pollutants
63,500 kg/h X 24 H X 365 Days = 556260000 kg/year
556260000 kg/year X 2.20462 pounds/kg =1226341921.2 pounds/year
1226341921.2 pounds/year / 2204.62 pounds = 20025360 tons/year.
Is my math correct and what do I need to determine the % exhaust mass is pollution.
https://preview.redd.it/w1c42fpk8weg1.png?width=996&format=png&auto=webp&s=27d44f84409caf2231dc82a82a360887f815e16f
https://preview.redd.it/ax15c2wr8weg1.png?width=1181&format=png&auto=webp&s=6daf27cdd1ccdc4722a8939b327c67b94de258bc
https://redd.it/1qjt5cf
@TheyDidTheMath
[Request] Is there a chance that there is someone in this world who has a 7 degrees of separation?
https://redd.it/1qjt4go
@TheyDidTheMath
request This is very important, how many European badgers could fit in the Colosseum in Rome?
It's as the title says, I need to know how many badgers could fit in there. I'm pretty sure a European badger is around 122 liters large, but I could be wrong.
EDIT: I meant specifically on the *inside* of the Colosseum, not the outside.
https://redd.it/1qjq86n
@TheyDidTheMath
[request]Diameter of a tree
https://redd.it/1qjawbw
@TheyDidTheMath
[Request] How tall he actually is?
https://redd.it/1qj806x
@TheyDidTheMath
[request] How much would this cost in 2026?
https://redd.it/1qiyl92
@TheyDidTheMath
[Self] Jury Nullification Math. If ~1/3 of your community would acquit you for a certain crime, then that crime is effectively LEGAL.
https://redd.it/1qepo2c
@TheyDidTheMath
Is anyone able to take on this impossible task?[Request]
https://redd.it/1ptc61k
@TheyDidTheMath
[Request] I’m not a mathologist, but could someone calculate the per-mile fatality rate of NASCAR vs. aviation?
https://redd.it/1pt2ynp
@TheyDidTheMath
[Request] How much energy would the GTA train need to move all these vehicles?
https://redd.it/1qkceua
@TheyDidTheMath
When Tony Montana stuck his face in the pile of coke at the end of Scarface and snorted, was this enough to kill an average person? [request]
https://redd.it/1qkba0i
@TheyDidTheMath
[Request] What WOULD happen?
https://redd.it/1qk8ibd
@TheyDidTheMath
[Request], chances of both players having same hand in 1v1 crib
https://redd.it/1qk4ruo
@TheyDidTheMath
[Request] How accurate is this claim? (I'm just curious about the water/energy usage, dont think we can slot in finishing 100 times over in an equation somewhere)
https://redd.it/1qk2hc3
@TheyDidTheMath
[Self] A Note on the Erdős–Straus Equation: No Pairwise Coprime Solutions
Hi everyone,
Consider the Erdős–Straus equation:
4/n = 1/x + 1/y + 1/z, n >= 2, x < y < z, n,x,y,z are natural numbers
We investigate the case where x, y, z are pairwise coprime natural numbers.
This assumption leads to a contradiction, so no such solutions exist.
---
1. Multiply through by nxyz (all natural numbers):
4xyz = n(xy + xz + yz)
2. Divide by x:
4yz = n(y + z) + n(yz)/x
Since gcd(x, yz) = 1, yz/x is integer only if x divides n.
Write:
n = ax, a is natural number
3. Substitute:
4yz = axy + axz + ayz
Divide by y:
4z = ax + az + a(xz)/y
Since gcd(y, xz) = 1, y divides a. Write:
a = by, b is natural number
Substitute back:
4z = bxy + bxz + byz
4. Divide by z:
4 = bx + by + b(xy)/z
Coprimality forces b = cz, c is natural number
Substitute:
4 = c(xy + xz + yz)
Since xy + xz + yz >= 3, no natural number c satisfies this. Contradiction.
---
Conclusion: There are no solutions to 4/n = 1/x + 1/y + 1/z with x < y < z, n,x,y,z natural numbers, such that x,y,z are pairwise coprime.
---
Remarks:
* All variables n,x,y,z,a,b,c are natural numbers.
* This argument only shows pairwise coprime denominators cannot occur; it does not classify all solutions.
* Further exploration could consider non-coprime cases or alternative decompositions.
Let me hear your opinions
https://redd.it/1qjy4bh
@TheyDidTheMath
Self Open a book at a random page, what may be the sum of the two page numbers on both sides? A.75 B.85 C.80
https://preview.redd.it/p0l5fj0hbveg1.png?width=885&format=png&auto=webp&s=65cb0a680962471f4f7daddd0feaee5938ecdeca
https://redd.it/1qjpxw3
@TheyDidTheMath
[Request] Pulled from a YouTube short. Does that actually match up?
https://redd.it/1qj5gje
@TheyDidTheMath
And they ask why men don’t live as long as women [request] Did he really drink the 14 shots of whiskey in less than an hour, if possible… how quickly did he eat the bananas? Sorry if there’s not enough info
https://redd.it/1qii85t
@TheyDidTheMath
What would be the bare minimum amount of food and water would one need to walk the Pan-Am highway? [Request]
https://redd.it/1qj8rym
@TheyDidTheMath
[Request] Ladder height
https://redd.it/1qjlkpm
@TheyDidTheMath
[Request] Can Someone Explain Why This Is Possible?
https://redd.it/1qes6sl
@TheyDidTheMath
[Request] is this true of any five points on a 2D plain? As in, will any five points have some quartic function that intersects all of them?
https://redd.it/1ptegfd
@TheyDidTheMath
[Request] Is this really 4, 90 degree, angles?
https://redd.it/1pt9xu6
@TheyDidTheMath
Request How do breakthrough EV batteries provide the same or more range for a vehicle as cars that use internal combustion?
I've read articles about breakthroughs in EV batteries that achieve about 800+ wh/kg in energy density, then states that it can provide EVs less than or more than 1000km of range.
What bothers me is that ICE fuels such as gasoline has an energy density of 12,000 wh/kg and yet I see statements that your average gas/diesel cars have a range of ±600 km depending on the vehicle.
Bonus question: will electric jet engines (like the microwave plasma one) be finally available after all the breakthroughs in battery energy density?
https://redd.it/1psx6vx
@TheyDidTheMath
