learn cool things through maths.
real numbers. surprising answers. a more interesting world.
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did you know...
you can tell how far away lightning is by counting seconds?
Sound travels about 5 seconds to reach you from 1 mile away.
weatherread moredid you know...
a bigger pizza is actually better value?
A little bit of division shows you that a 14″ pizza gives you more pizza per pound than a 10″.
moneyread moredid you know...
speeding doesn’t save as much time as you think?
On a 100 mile trip, going 80 mph instead of 60 mph only saves you 25 minutes.
physicsread moredid you know...
TikTok has to predict whether you’ll swipe away?
It uses machine learning to guess how long you’ll watch — and what you’ll like next — in real time.
algorithmsread moredid you know...
Google Maps uses graph maths to find the fastest route?
Your city is a giant network of roads (nodes and edges), and it runs clever algorithms like Dijkstra’s to find the best path.
internetread moredid you know...
a day on Venus is longer than a year on Venus?
Venus takes 243 Earth days to rotate once, but only 225 days to orbit the Sun.
spaceread moredid you know...
you can estimate a building’s height using its shadow?
the sun hits you and the building at the same angle, so your height and shadow are a portable measuring stick.
everydayread moredid you know...
you can calculate how far away the horizon is?
standing at sea level, the horizon is only about 5 km away. from a cliff top it can be ten times that.
natureread moredid you know...
Spotify can measure how similar two songs are?
songs and listeners can be placed as points in a giant mathematical space — and taste becomes a matter of distance.
algorithmsread moredid you know...
airlines overbook flights on purpose?
a predictable share of passengers never show up, so airlines sell the empty seats twice — and probability tells them how far to push it.
probabilityread moredid you know...
your bank spots fraud in milliseconds?
every payment is scored against your own history — where, when, how much, how often — before it’s approved.
airead moredid you know...
compound interest grows money absurdly fast?
interest earning interest is exponential growth — and exponential growth is the thing human intuition is worst at.
moneyread moredid you know...
23 people can be enough for a birthday match?
a small room hides a surprisingly large number of pairs.
probabilityread moredid you know...
switching doors can double your chances?
one prize, three doors, and a host who knows more than you do.
probabilityread moredid you know...
a coin has no memory of its last flip?
five heads in a row do not make a fair coin owe you tails.
probabilityread moredid you know...
six numbers can hide millions of combinations?
a tiny-looking ticket sits inside a huge mathematical space.
probabilityread moredid you know...
an accurate alarm can usually be wrong?
when something is rare, the ordinary cases can swamp the signal.
probabilityread moredid you know...
one is often the most common first digit?
some collections of numbers have a surprisingly lopsided favourite.
weirdread moredid you know...
a deck of cards has an absurd number of orders?
52 ordinary cards create a number with 68 digits.
probabilityread moredid you know...
random arrivals make long bus gaps find you?
you are more likely to land inside a long gap than a short one.
everydayread moredid you know...
a new road can make everyone's journey slower?
a shortcut for each driver can become a bottleneck for everyone.
algorithmsread moredid you know...
a million items can take just twenty checks?
every good question throws away half the possibilities.
algorithmsread moredid you know...
a damaged QR code can still know the answer?
some of those little squares carry a mathematical backup.
technologyread moredid you know...
your GPS needs Einstein to keep good time?
satellite clocks tick differently, and tiny timing errors mean big distances.
technologyread moredid you know...
the internet sends your photo in little pieces?
your message travels like a stack of labelled parcels.
internetread moredid you know...
one random character can multiply the possibilities?
length grows a search space by multiplication, not addition.
technologyread moredid you know...
a JPEG saves space by letting details go?
your photo becomes a recipe of patterns, with some ingredients rounded away.
technologyread moredid you know...
headphones can fight noise with more sound?
an upside-down pressure wave can make the world quieter.
technologyread moredid you know...
a bubble is solving a geometry problem?
the roundest answer uses the least surface to hold the air.
natureread moredid you know...
hexagons make beautifully economical honeycombs?
six sides pack equal spaces together with very little wall.
natureread moredid you know...
sunflower spirals hide a special angle?
a turn of about 137.5 degrees keeps new growth from lining up.
natureread moredid you know...
a giant ant would need a serious redesign?
doubling its length makes eight times the animal.
natureread moredid you know...
a rainbow is really a circle?
the ground hides the rest of the geometry.
weatherread moredid you know...
blue skies and red sunsets share one explanation?
air scatters short wavelengths much more strongly.
weatherread moredid you know...
a snowflake's six-fold shape starts with molecules?
tiny crystal rules become patterns you can see.
natureread moredid you know...
a hot road can borrow a piece of the sky?
bent light can put the sky where you expect the ground.
weatherread moredid you know...
the Moon is slowly moving away from us?
Earth's tides pass a little rotational energy into the Moon's orbit.
spaceread moredid you know...
a tiny Moon can hide an enormous Sun?
apparent size depends on distance as well as diameter.
spaceread moredid you know...
summer comes from a tilt, not a closer Sun?
tilted sunlight changes both the length and the intensity of a day.
spaceread moredid you know...
astronauts float because they keep falling?
their spacecraft is falling around Earth right alongside them.
spaceread moredid you know...
every star you see is a message from the past?
light travels fast, but the universe is very big.
spaceread moredid you know...
a tiny dip in starlight can reveal a planet?
a distant world's silhouette can give away its size.
spaceread moredid you know...
42 imaginary paper folds could reach the Moon?
doubling starts quietly, then gets completely out of hand.
weirdread moredid you know...
every flat world map has to distort something?
flattening a sphere always asks you to make a trade-off.
everydayread moredid you know...
a shorter ruler can make a coastline longer?
smaller measurements discover bends that bigger ones skip.
weirdread moredid you know...
a longer swing keeps a slower rhythm?
for small swings, length matters much more than the bob's mass.
physicsread moredid you know...
an octave is a doubling you can hear?
440 vibrations a second and 880 belong to the same musical family.
physicsread moredid you know...
your microwave has invisible hot and cold spots?
reflected waves can reinforce each other in some places and cancel in others.
everydayread moredid you know...
two twenty-percent discounts do not make forty?
the second discount works on a price that has already shrunk.
moneyread moredid you know...
hot coffee loses its heat faster at the start?
the gap between your drink and the room drives the cooling.
everydayread moredid you know...
a satellite dish uses geometry to catch a whisper?
one carefully chosen curve gathers faint signals into a single spot.
technologyread more