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This month: Stage 1&2Stage 2&3Stage 3&4Stage 4&5switch to US educational language

Mind Reading

Problem | Teachers' Notes | Hint | Solution | Printable page |
Stage: 3 Challenge Level: Challenge Level:1
Think of a number, Add one, Double it, Take away 3, Add the number you first thought of, Add 7, divide by 3, take away the number you first thought of, You should now be left with 2. How do I know?
Games. Visualising. smartphone. Number operations - generally. Interactivities. Workshop. Mathematical reasoning & proof. Creating expressions/formulae. Generalising. Algebra - generally.

Published January 2004.

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