Math & Numbers Facts for Kids
Mind-bending number facts
In a magic square, every row, column, and diagonal adds up to the same total. The oldest known magic square, called the Lo Shu, comes from ancient China and dates back over 4,000 years.
A palindrome number reads the same forwards and backwards, such as 121 or 1,221. The year 2002 was a rare palindrome year.
Euler's number, written as e, is approximately 2.71828 and is used to describe natural growth, such as population growth and compound interest. Like pi, its decimal places never repeat.
If you placed one grain of wheat on the first chess square and doubled it on each square, the total on all 64 squares would be about 18 quintillion grains β more wheat than has ever been grown in history.
The abacus is one of the oldest calculating tools in history, used in ancient Mesopotamia, China, and Rome. Skilled users can solve complex sums faster than a calculator.
Negative numbers were first used in ancient China to represent debt on counting boards. European mathematicians were slow to accept them, calling them 'absurd' as late as the 1600s.
Each time you flip a fair coin, the probability of getting heads is exactly one half, or 50%. Previous flips have no effect on the next one β the coin has no memory.
As of 2024, the largest known prime number has over 41 million digits. Finding huge prime numbers is important for keeping internet passwords and bank details secure.
Among all three-dimensional shapes with the same volume, a sphere has the smallest surface area. This is why soap bubbles are always round.
Archimedes calculated an accurate estimate of pi around 250 BC by drawing polygons inside and outside a circle. He showed pi lies between 3 10/71 and 3 1/7.