Four thousand years ago, the Babylonians invented multiplication. Last month, mathematicians perfected it. On March 18, two researchers described the fastest method ever discovered for multiplying two ...

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Multiplication is calculating the sum of groups of the same size. There are lots of ways to build and describe multiplication problems. Using repeated addition, you can add equal groups together, one ...

Find out what multiples are and how to sort multiples of 2 and 5. Doubling numbers Learn how to make doubles using ten frames, addition and multiplication. Counting in twos, threes, fives and tens ...