Math & Numbers Facts for Kids

Doing math with Roman numerals was incredibly difficult, which is why the abacus was so important in ancient Rome.

We buy eggs by the dozen (12) because 12 can be evenly divided by 2, 3, 4, and 6, making it super useful for sharing.

There are only 5 Platonic solids — 3D shapes where every face is the same regular polygon. The ancient Greeks discovered all five.

Srinivasa Ramanujan was a self-taught math genius from India who sent letters full of brilliant formulas to Cambridge — many are still being studied.

If you put 1 grain of rice on the first square of a chessboard and double it each square, you'd need over 18 quintillion grains for the last square.

Pascal's triangle hides tons of number patterns — it contains the Fibonacci sequence, powers of 2, and triangular numbers.

Catalan numbers tell you how many ways people around a table can shake hands without any arms crossing.

The multiplication sign (×) was introduced in 1631 by English mathematician William Oughtred.

Imaginary numbers (based on the square root of -1) sound made up, but they're essential for engineering and electronics.

The pigeonhole principle proves that in London, at least two people must have exactly the same number of hairs on their head.