When I was in middle school, I had a classmate who would look at trigonometric functions and yell, "I will never need these!" A lot of us had similar thoughts but wouldn’t say them out loud. But there’s a subreddit that proves otherwise.

‘They Did the Math’ is full of useless yet fascinating calculations for all of us normies who can’t crunch the numbers ourselves. From how many flies it would take to lift an average person to how fast a Godzilla-sized snail would crawl, here are some of the most interesting questions—and answers—we found scrolling through its feed.

**

SecondaryWombat: So it looks like my laptop take about 50g of weight to press a key (Source: I put my laptop on a scale and pressed keys). Standing still a cat stands on all four legs (I am choosing to extrapolate the existence of this kitten’s other back leg). So while not moving, with its paws on only one single key each (which we can see from the photo is not correct) the kitten would need to weigh 50x4=200 under 200 g. However, it looks like each paw that we can see is on a minimum of 2 keys and that changes things substantially. 2.5 keys/leg x 50 g/key x 4 leg/cat = 500 grams/cat, and look the units cancel, so that means my math is right. A 500 gram kitten is about 5 weeks old, and that also looks correct visually.

lvbbara Report

RELATED:

**

innnerness: If we take it literally, assuming the snail is roughly the height of a five-story building (say, 15 meters tall), that’s about 1,500 times larger than a typical garden snail (~1 cm tall). Speed scales roughly with the square root of linear size if muscle power and proportions stay the same. So: Average snail speed: ~0.03 mph (0.048 km/h). Square root of 1,500 ≈ 39. 0.03 mph × 39 ≈ 1.2 mph (about 2 km/h So, this Godzilla-sized snail would crawl at a slow walking pace, fast enough to make “Walk for your lives!” actually sound like decent advice.

zsigubigula Report

**

wayoverpaid: This assumes a single elimination, best of one tournament. Say something like rock paper scissors or a coin flip. You need one round for the finals. So one game for the finals. Semifinals has four people, quarter finals has eight people. Each round cuts the field in half. The winner only needs to win one round from that game. With 33 rounds, you get 233 people. That’s 8,589,934,592. World population is under 8.3 billion. So the winner MIGHT get a bye in the first round, and only have 32 games. But 33 games guarantees the win.

Pabloescobarg Report

**

gurneyguy101: 32kg/m3, 5.5m x 0.5m x 1.5m = 3.3m3 —> x 32 = 105kg Hmm, I think it’s fair to say something’s gone wrong here. I reckon the sword is hollow Edit: or the sword is photoshop, in which case it would weigh 0kg

broautism552 Report

**

electricsoldier96: They did it on MythBusters, with 3500 balloons and a 44lbs child. If this is a 20lbs Dachshund, it would took 3500 / (44 /20) = 1590 balloons.

Fatteo Report

**

PolyPorcupine:

Spotify says it has 100 million songs and 6 million podcasts, average length of a song is 3 minutes, the average length of a podcast episode is 41 minutes, and the average amount of episodes of a podcast are 10. Also they have 350k audiobooks, at an average length of 10 hours. So you have 300,000,000 minutes of song And 2,460,000,000 minutes of podcasts and another 210,000,000 minutes of audiobooks. Totaling around 3 billion minutes of content. Calculating it’s around 5707 years, if you listen to it at 5707x speed you’ll be done in a year, easy. Though google also says that around 100K songs are added every day, so once you are done with those you’ll have another ~300k minutes every day.

urlocalweedman Report

**

Butterpye: Some company estimated employees will take a 20 minute break during their work hours, they figured there would be 84 million workers on that day, and they multiplied the amount of time with the hourly wage for people over 16 and which is like $24 or so dollars and got $694 million.

transvangelical , OomGielie Report

**

Nahanoj_Zavizad: Assuming it’s approximately 1.5m in each direction, and solid. Tungsten density is 19300 KG per M3 So it would end up weighing about 60-70 Tonnes. carajillu: mtu in metals trading is equivalent to 10kg, not 1000, because it refers to 1000 kg of the brute ore which is around 10kg of pure metal. So, 70 tones is 7000 mtu, which cost in current prices around 330$, which results in 7000*330= 2.310.000$

duonganh2306 Report

**

jeffscience: This is 10x the estimated temperature at the site of the nuclear blast at Hiroshima. The turkey would cease to exist in any recognizable form.

howie_hua , gimme_your_liver_now Report

**

GIRose: Jeff Bezos’ net worth, ~$210,000,000,000 210 billion/7000 = 30,000,000 hours to surpass him. There are 8,760 hours per year So ~3,424 years to catch up to Jeff Bezos’ current wealth at $7000 an hour if it was expanding at it’s current rate, literally never because it expands by ~$8,000,000 an hour.

thegreatola , Pocomics Report

**

anon:

This river looks to be 100 miles wide, and stretches about 2700 miles. lets give it an average depth of 15 feet. converting everything to feet 15 x 528000 x 142560000 = 1,129,075,200,000,000 cubic feet Assuming you had a human who could work 8 hours straight without tiring and can shovel 1 cubic foot every 15 seconds (with a crew to help move the dirt he shovels). This would take 282,268,800,000,000 minutes or 4,704,480,000,000 hours or 196,020,000,000 days or 537,041,096 years.

BiLeftHanded Report

**

Yes N64 cartridges vary between 4-64Mb

388x 64= 24,832Mb so 24-25Gb if they were all max size.

So they would easily fit on, especially once you account for the smaller games.

Informal-Bus-9679 Report

**

Surly_Dwarf:

No. Almost 5 million flies (or 437k bumble bees, or 65k monarch butterflies, or 10k hummingbirds, or 2.9k sparrows, or 1.9k fruit bats, or 441 pigeons, or 25 bald eagles) to lift a 110 pound person.

charminglyantiquated , Annath0901 Report

**

Appropriate-Falcon75: The area is about 82,000 km2 , and there are about 8.2bn people on earth. Which means that each person gets about 10m2 . So, if you arranged people in a grid, there would be about 3m (or 10ft) between each person.

Apprehensive_Oven_22 Report

**

ModeMysterious3207: Assume typical sunglasses with a 30% transmission. Is that seven pairs of sunglasses? 0.37 is 0.02% transmission. Recommended for solar filters is 0.001%, so, not dark enough. Eye damage? Depends on how long you look

rubentheboy Report

**

STK_Pixle: A penny made before 1982 is 3.11 grams and consists of 95% copper, so taking 95% of 3.11 is around 2.95 grams. 1 penny = 2.95 grams of copper There are approximately 454 grams in a pound, and Lady Liberty is made of 62,000 pounds of copper. 454/2.95 = 153.9, which would round up to 154 pennies for one pound of copper. 154 × 62000 = 9548000 So in total, you would need 9,548,000 pre-1982 pennies, or $95,480 in face value, to make a second statue from just pennies.

dumbbassonline , Suitable-Wealth4524 Report

**

Public-Eagle6992: I‘m not sure how exactly the statement is meant so I’ll interpret it one way but also state other ways how it could be interpreted. "The ten richest men…" could either mean each of them individually or all of them combined. I‘ll go with individually. "Their riches wealth" I assume this means net worth "Richer than 99%" could mean the wealth of the 99% combined, could mean the average wealth of the 99% or could mean the highest amount of money anyone in the 99% has. I‘ll go with highest Wealth of 10th richest person: 121 billion. -99.999% that’s 1.21 million. 1.1% of adults have at least 1 million, so when having 1 million, you can still be in the lowest 99%. So it might be true, it’s close.

RBReich , RashoRash Report

**

Kionimom1: It really depends on what wax the Candle is made of and how the wick is Placed inside Lets say its paraffin wax and the size of the candle is 1 cubicmeter meaning 1000000 ccm. The density is 0,9 g/ccm. So the candle would be around 900 kg (i have the feeling there is a mistake here). A normal paraffin candle burns about 7,5 grams per hour so it should burn for about 120000 hours or 13.6 years, considering it doesnt heat up too much Also, if the candle is Constantly heating up for hours it burns down a lot faster than lighting it on and extinguish it every half hour. Thats also why you shouldnt keep normal size candles lot for more than 5 hours because the heat can potentially get so Hot nearby stuff Catches fire.

jackcorrbit , kc_white Report

**

**shelmich: **If his weight doubles every 3 months, then by the time he hits 10, he’ll have doubled 40 times. So if he’s 7.5 trillion when he’s 10, then we can solve for his birth weight in the following equation: 7.5 trillion lbs = x * 240 This gives x = 6.8 lbs, a very reasonable birth weight.

pronounced_kyle , stee4vendetta Report

**

whynotthebest: Math is correct but the words are not. This is similar to stating that the 2010 federal minimum wage of $7.25/hr could buy you 72.5 Bitcoin after an hour, and since 72.5 Bitcoin is now worth $7,568,659.25, then federal minimum wage was $7,568,659.25 in 2010.

Separate_Draft4887 Report

**

tutorcontrol: Approximately, yes. Average distance is 12.5 light minutes for a ping of 1.5 million ignoring the electronics. 182 light seconds is the closest recorded position for a ping of 364,000, also as a "mirror bounce". This is why the rover has some longer commands and autonomous capabilities to break the control loop latency problem. So far, nothing with a 100 ms control loop has tried to chase it, and rocks tend to have effective pings around 3 e 12, so 1e7 is pretty good.

sotobet0509 Report

**

**e-war-woo-woo: **Tesco is slightly over on Google figures for 2024 3128 million profit, 330,000 world wide employees = 9478 per employees. So if they paid 10k extra they’d be makings loss. But they could defo do 5k extra and still make a healthy profit.

BladeoftheS , MMplayzYT Report

**

Warm-Finance8400: That would translate to the average person being drunk 0.7% of the time. A week has 168 hours, 0.7% of that would be ≈ 1.2 hours per week drunk. Seems reasonable to me.

leppernfriends Report

**

Ok_Programmer_4449: The internet currently stores about 1.4x1024 bits, and it takes about 100,000 electrons to store a bit in an SDRAM, so if all the data on the internet were stored in SDRAM you’re talking about 1.4x1029 electrons, or 140 thousand trillion trillion electrons which would weigh about 130 grams. So you’re in the right ballpark. It’s a few strawberries. But most data on the internet is not stored in SDRAM. Most data is still stored in the alignment of iron atoms on mechanical hard disks. It takes about 20,000 iron atoms to store a bit. So you are talking 2.8x1028 iron atoms, which weighs about 2.6 metric tons, which is about the weight of 52000 strawberries.

alootikkiprotocol Report

** 

UncleCeiling: There are about 13,500 McDonald’s restaurants, each with an average of 50 employees (As per McDonald’s 2023 numbers). A large McDonald’s fry has about 80 fries in it (numbers seem to vary from 75-90 depending on where you are getting your fries, and it costs $5 (note that that’s retail, not what the company actually pays) for a total of $0.0625 per fry. So if every employee (not just the ones on staff) ate a single fry every day it would cost the company $42,187.50 based on retail fry numbers. For individual stores, it wouldn’t even average the price of a large fry.

lazertittiesrrad Report

**

ElevationAV: Assuming we’re doing a 1 time tax on Bezos’ net worth of ~250 Billion, that gives us 11.75 Billion once. Free college in the US is estimated to cost between $28B and $75B per year; Sanders plan estimates at least $48B per year; so no, a 4.7% tax on just Bezos wouldn’t even provide half the funding for a single year.

reddit.com Report

**

Solondthewookiee: It would depend on the exact year and how they calculate purchasing power. Here’s the method I used: Median home price 1970: $17,000 Median home price 2024: $420,000 Minimum wage 1970: $1.45/hr Min wage as a percentage of home price 1970 = 1.45/17000 = 8.53e-5 Multiplying that by 2024 home price: (8.53e-5)(420000) = 35.82. So not $66/hr, but several times the current minimum wage.

Lurkie2 Report

**

escaping-to-space: Aircraft carrier ~ 13 Billion American homeless ~ 800 thousand High-density construction cost ~ $350/square foot 13B/800K = $16,250 available per person Divided by 350/sqft = 46.4 sqft per person (of new construction)

So depending on exact construction costs or repurposing old buildings, you could get a ~5x10 room per person. Not enough to house everyone, but I suppose technically enough to shelter everyone. Since that room doesn’t have space for plumbing or kitchen, you might be able to construct for less than $350/sqft and then maybe squeeze out a bigger room or have some shared bathroom/cooking areas but that still isn’t housing.

Though, while I know we pump a ton of money into military, the price of one ship did give more per person than I initially would have guessed.

DTMICNow , Depressed223 Report

**

u/dr_pickles69: According to some sources, the average cost of a kidney transplant in the United States was around $442,500 in 2020. However, this does not reflect the actual price that a donor would receive, as most of the cost goes to the hospital, the surgeon, the recipient, and other expenses. On the black market, a kidney donor might get anywhere from $1,000 to $200,000, depending on the country and the demand. If we take the average of these figures, we can estimate that a kidney donor on the black market would make about $50,000 per kidney. Therefore, if Deadpool sold 500 of his kidneys, he would make about $25 million.

Ornery_Perspective54 Report

**

A_Martian_Potato: This is a very well known mathematical problem. The post is correct. It’s one every student in a undergrad level statistics course does. I won’t go over the math to prove it, you can see that in the wikipedia page if you want, but the thing to keep in mind is that you shouldn’t be comparing the number of people to the number of days in a year. You should be comparing the number of PAIRS of people to the number of days in a year. In a room with 23 people there are 253 pairs you can make. In a room with 75 people there are 2775.

DependentCollar8541 Report

**

For each beer a single American drinks, a brit would have to drink nearly 5 based on numbers alone.

The_not-so_chosen_1 Report

**

antilopelore:

I converted the picture you posted into a bitmap to make it simpler. I replaced the remaining cake with white and the part you cut off with black. Then, I simply counted the number of pixels of both colors, giving me the following results: White Pixels: 127,200 Black Pixels: 47,753 Which totals: 174,953 pixels in total. After that, I simply calculated the ratio of the number of black pixels to the total number of pixels. 47,753 / 174,953 Which gives us: 0.2729 This means that what you cut off was 27.29% of the total cake.

timmyboy87 Report

**

Rhuobhe26: It would be priceless beyond belief a literal one of a kind in the world eclipsing all other stones. The original Cullinan stone, the largest and possibly most famous of all diamonds was an uncut stone 4 inches long and about 3,100 carats. It is beyond value and was cut into 9 large and 96 smaller stones the largest of which is 530 carats. If the diamond was actually the full 4 inches in size or 100mm, with a deep cut then it would be 4,800 carats. The most expensive diamond ever sold at Auction was the CTF Pink Star, it sold in 2017 by Sotheby’s for $71.2 million and was 59.60 carats. Now you can’t compare the two, but just using those numbers that’s $1.19 million per carat. So between 2,624 to 4,800 carats at the same price...$3.13 billion to $5.73 billion.

IndividualRoom203 Report

**

Angzt: Let’s go with the following assumptions: Rat lifespans are around 2-4 years, so we can (kind of) ignore them dying off. Rat pregnancies last around 25 days, with a few days recovery before the next pregnancy, let’s round that up to 30 days. Rats reach adulthood at around 60 days. The size of a rat litter is around 6 to 18, so let’s go with an average of 12. Let’s also only look at the female rat population and then double at the end. It’ll make things a bit easier. So our litter size is only 6. Since our pregnancy and time to adulthood are both divisible by 30, let’s go with 30 days as our time period. Then 3 years are 365 * 3 / 30 = 36.5, so 36 time periods. Now, we need to track 2 variables: The number of adult femal rats (a) and the number of newborn female baby rats (b) in relation to our time periods. We know that we start with 1 adult female rat and 0 babies. So: a(0) = 1 b(0) = 0 We also know that the number of adults at any given time is the number of adults of the previous time period plus all the newly matured rats. The latter being the baby rats from 2 periods ago. So: a(t) = a(t-1) + b(t-2) Finally, the number of newborn rats is simply 6 times the number of adult females in the preceding period: b(t) = 6 * a(t-1). As you can see, we actually vastly exceed 482 million rats by the 36th time period. In fact, we get up to 2.7 trillion adult rats.

Desh1ck Report

**

Pretentious-Polymath: Exactly enough so that it would sink when trying to use it the regular boating way. The buoancy in that setup is mass of displaced water minus mass of the boat. Volumes for boats can differ, but this should be around 2500 litres, so 2.5 tons of weight to stay underwater like that.

zaiguai047 Report

**

james_pic: I’ve seen YouTube videos where they manage to get Mentos and Coke jets about 10m into the air, which would give the jet an exhaust velocity of 14m/s. Wikipedia tells me low earth orbit needs a Δv of about 9.5km/s. Plugging these numbers into the Tsiolkovsky rocket equation gives a wet mass of 2.5 * 10^297 kg. The observable universe has a total mass of 1.5 x 10^53 kg.

th0masm0re Report

**

Ritterbruder2: A sphere has the lowest surface area to volume ratio of any shape. It’s going to have the lowest glaze to dough ratio of any pastry.

Salt-Sound2705 Report

**

CHG__: Assuming a paint layer is 100μm thick it would take 10,000 layers to equal 1 meter of thickness, so 5 meters would be 50,000 layers.

Rawshaque Report

**

nog642: It would work, it would just make the water come out of your faucet a bit slower and wouldn’t generate much power. Typical flow rate for a kitchen faucet is 2.2 gallons per minute say. That’s 139 grams of water per second. And let’s overestimate the velocity and say it’s 3 m/s (6.7 mph). Then the kinetic energy of 139 g of water at that speed is 0.63 J, so the max power generated would be 0.63 W (and it would be less because we’re overestimating and a turbine can’t capture all the energy). A 5 V USB charger drawing 1 A, which is what those really slow basic phone chargers with none of the faster charging capabilities draw, is already using 5 W. So you couldn’t even charge a phone on this if you had the water running constantly. Maybe you could charge your phone while you run your bath. But what’s the point of that?

Repulsive-Loan5215 Report

**

Martensite_Fanclub: I used to work in solar and this question isn’t easy to answer - there are just too many variables. Cost and generation are affected by: location, time of year, panel crystallinity, spacing, and many other factors... But if you need a rough estimate, we were able to get about 1.1 MW (or about 1.72 GWh/yr) (or about $2.20 per Watt after tax credits, etc) on a 315-space parking garage roof in the southern Florida region. These were 3,000 monocrystalline panels (more efficient but more expensive) and ofc these were closer to the equator and get more sun so not everywhere would generate as much. Use these numbers per parking space as a rough estimate if you’re in a similar latitude and adjust energy generated down by 5-30% if you’re staying in the US (although using Solar Map is more accurate. For example, you may get about 12.79 MW/4.37GWh/yr for 800 parking spaces (or the average Walmart parking lot) in south Florida, which is enough to support ~415 homes year-round, which is probably what you really wanted to know.

abhitooth Report

**

**VincentGrinn: **the numbers are more or less right, 6k for busses per hour per lane is abit higher than i normally see but not by much a lane of car traffic can move about 1,500 people per hour per lane, but traffic lights limit that significantly, 1100 might be an overestimate walking is particularly hard to work out, some things ive seen say 15,000 per hour in a 3.5m wide space, but its rare to have so many people walking anyway good street design definitely is just a matter of maths though

Bathroom_Spiritual Report

**

PacNWDad: Assuming the diameter of the Dum-Dum is 2 cm, that is about 80 grams of U-235. 80g of uranium will release about 6 x 1012 joules of energy in a fission reaction. The average American uses about 3 x 1011 joules of energy per year for all use (not just home electricity, but transportation, workplace, share of industrial production, etc.). That would mean the uranium can provide about 20 years of an average American’s energy consumption. So, yeah this is in the ballpark, although about 1/4th what would actually be needed for a full 84 years. It would be more like 300g. Note that this is a little misleading, since U-235 is only about 0.7% of naturally occurring uranium. So actually, they would need to process about 42 kg of uranium to get the 300g of U-235.

AssociationIcy5963 Report

**

somehugefrigginguy: I’m not a car guy, but best I can tell that is a 2019 Lamborghini Huracan which gets about 15 miles per gallon. The tank on top looks like a 275 gallon IBC tank, so ignoring aerodynamic effects it would add about 4,125 miles of range. That tank mounted in that orientation adds approximately 13 ft² of frontal cross section plus parasite drag so at highway speeds this could reduce fuel economy by as much as 50%. So if we assume a fuel economy of 7.5 mpg, that tank would add 2,062 miles of range.

brilliant31508 Report

**

Solondthewookiee: No. The design power of Reactor 4 was 3,200 MW. Over 40 years, it would release 4.0e18J, which is 20 times the energy released by Tsar Bomba. Since Chernobyl did not culminate in the largest nuclear explosion in history by an order of magnitude, we can say that the meme is inaccurate. The last reading from the instruments during the accident gave a power reading of over 30,000 MW. The reactor exploded almost immediately after, but it puts us in the ballpark of 10x energy production.

Rsthegoat Report

**

**roge-: **At 0.349 cm3 per penny, 60 million pennies would have an aggregate volume of 20.94 million cubic centimeters or 20,940 liters. As for how large of a container you would need to fit all of those pennies, its capacity would have to be greater than that, since discs won’t pack perfectly.

nycguy12392 Report

**

andrew_calcs: No. It’s a paradox. B is not a fraction of 4 so can never be correct in a 4 element set with discrete correct answers. For C to be correct you would need 2 elements of the set to be 50%, so C cannot be correct. For either A or D to be correct you would need 1 element of the set to be 25%. Since there are two, neither can be correct.

K4czoRRR Report

**

John12345678991: Well that’s over 10x increase so everything would immediately weigh like 12 times more. Every building would collapse cuz they use factor of safeties of like 2-4. Everyone standing would break most of their bones. If ur just laying on the ground outside u might be ok.

Upstairs-Ad-4705 Report

**

A: 24*365

B: 60*60*24

C: 365*10

D: 60*24*7

We see that A > C and B > D. Both A and B contain 24. Lets remove it.

A’: 365 B’: 60*60

B is bigger by one order of magnitude.

reddit.com Report

**

Single_Blueberry: A human chain is probably the most efficient way if you HAVE to use this many people, because they would block each other if they moved. Could you do it just as quickly or quicker with much fewer people? Probably. More importantly though, it’s fun to do it this way and a good opportunity to socialize.

**ya_mamas_tiddies: **This is 100% the most efficient way, as none of those folks are getting paid for this. What can be more efficient than free manual labor

DarkGraphite Report

**

52!

8.0658175170943900791e+67

52 cards, the first card in the deck can be any of the 52, the second can be any of the remaining 51 and so on. That is 52!

iFreaK72 Report

**

natesplace19010:

It’s basically 99.99% fatal at 200 ft or more. That said, there’s always a chance but it would involve an act of god like a hugely perfect gust of wind or the water randomly getting airated by underwater gasses.

yesyesnopeyesyes Report

**

Electronic_Finance34:

There are 100 people, and 99 are lefties. That means there is 1 right handed person. What would cause the 1 right handed person to double in representation from 1 to 2%? If the one right handed person was in a room with 49 lefties, they would then be 2% of the total. So 50 lefties need to exit the room.

thehollowsimp Report

** ![Colossal obsidian sphere concept in San Francisco Bay illustrating weirdest math problems solved with humor and scale.](https://www.boredpanda.com/blog/wp-content/uploads/2025/12/download-6-6942caf667321-png__700.jpg “Colossal obsidian sphere concept in San Francisco Bay illustrating weirdest math problems solved with humor and scal