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Puzzle of the Day

These puzzles are also printed in Eight days a week, a booklet published by the Association of Teachers of Mathematics.

Think of a number, multiply it by 5 and add 3. I could find your number if you gave me the answer and I first took away 3 then divided by 5. It is always possible to find out the original number by reversing the steps, so try giving other people puzzles like this and work out what number they started with.

Answer: 7