Math & Numbers Facts for Kids
Mind-bending number facts
When you multiply any single-digit number by 9, the digits of the answer always add up to 9. For example, 9 x 7 = 63, and 6 + 3 = 9!
The golden spiral, derived from the golden ratio, appears in sunflower seed heads, nautilus shells, and even the arms of spiral galaxies.
In 1736, Leonhard Euler proved it was impossible to walk across all seven bridges of Konigsberg exactly once and return to the starting point. This puzzle launched the entire field of graph theory.
The Romans had no symbol for zero. The concept of zero as a number was developed independently in India and Mesoamerica and later spread across the world.
Over 2,000 years ago, the Greek mathematician Euclid proved that there is no largest prime number β there are infinitely many of them, stretching on forever.
Music and maths are closely connected. Musical notes follow mathematical ratios β for example, an octave is a 2:1 frequency ratio, and a perfect fifth is 3:2.
In a class of just 23 pupils, there is a greater than 50% chance that two of them share the same birthday. With 70 pupils, the probability jumps to 99.9%!
Dividing zero by zero is 'undefined' in mathematics because it could logically equal any number, making it impossible to assign a single answer.
The measured length of a coastline depends on the scale of your ruler. The smaller the ruler, the longer the coastline becomes, because you measure more tiny nooks and crannies. This is called the coastline paradox.
Even and odd numbers take turns forever: 1, 2, 3, 4, 5, 6... This simple pattern goes on without end, no matter how high you count!