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Pelmathism is like Pelmanism. The computer starts with $16$ cards, face down. Alternatively you can choose the number of cards you want to play with.
The cards come in pairs and you start with $100$ points. You click on two cards to flip them over, if they match you win $50$ points, if not you lose $5$ points for each card. Try again. Remember where the different numbers are so when you turn each card, if you remember where its partner is you can make the match. The game finishes when you have matched all the pairs.
You are playing this game on the computer but not against the computer. Chance comes into it, but it is a game of skill and concentration and knowing your numbers. What is the maximum score for $16$ cards? How close can you get to it? We think you are doing extremely well to get a score of $400$ but it is possible, with luck on your side, to do even better than that.
Where does the maths come in? Here is a fun way to practise multiplication tables. The object is to find the matching pairs as quickly as possible to get the highest score. The numbers on these cards are also represented by the products of two numbers. For example you have to match $14$ with $2 \times 7$ or with $7\times 2$ and you have to match $20$ with $2 \times 10$ or $10 \times 2$ or $4 \times 5$ or $5 \times 4$.
To download printable versions of this game use the links below. If you print double-sided, the cards will each have an NRICH logo on the back. If you would prefer them to be blank on the back, please just print the first page.