Dr Maths: One + One = Two
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Dr Maths: One + One = Two


Each letter represents a different digit and your challenge is to discover which digit each letter represents. Conor 14, told me this puzzle at Irish Maths Week.

In this type of puzzle you are given an addition sum with the letters of the alphabet replacing the digits. To solve the puzzle you have to work out which digit is represented by each letter and thus restore the original calculation. No one knows for sure when this type of puzzle originated, but it seems to have been well-known in India and China at least a thousand years ago.

A possible solution to Conor’s puzzle is 231+ 231 = 462 and there are also other answers which work in the same way. Why not see if you can find more? With some of the answers you will need to think outside the box and use carry overs, for example 236 + 236 = 472. There are in fact 16 different possible solutions to this puzzle.

Can you think of a different word puzzle that works in the same way as this one?

I have always thought that puzzles are a great way to improve mathematical understanding and from a young age it is good for children to exercise their brains with puzzles. Research has shown that mental exercise such as maths puzzles improves overall problem solving ability.

For Irish Maths Week last year I created a maths activities section on their website which is free for anyone to use. It contains website links and interesting books on puzzles, logic problems, maths magic, maths art, code breaking and much more. See www.mathsweek.ie/2011/puzzles

Here is a puzzle for you to try:


Each letter represents a different digit and your challenge is to discover which digit each letter represents. There is more than one answer to this puzzle.

Do you have a maths question or problem? Write to Dr Maths: DRMaths@hotmail.co.uk and your question could appear in BrainBox’s next Maths newsletter.

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