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Here are three 'tricks' to amaze your friends.
But the really clever trick is explaining to them why these 'tricks' are maths and not magic. Like all good magicians, you should practise by trying them. Can you explain how they work?
|This trick will impress even your maths teacher.|
Try this with a different
starting number. Did you get a different result? Why does this
Write the answer on a piece of paper without letting anybody see it and seal it in an envelope. Have somebody hold the envelope and at the end ask them to open it and reveal the number you wrote at the beginning. Wow, Magic!
|Guess how much money people have in their pockets!|
Without giving you any information, ask a friend to count the value of some coins and write the amount on a piece of paper. Then ask your friend to:
For the grand finale, you ask for the final answer. Take off the last digit and you will be able to work out how much the coins are worth!
|Amaze your audience by working out not only their age but also
what size shoe they wear! Wow them even more by telling them how
the maths works.
Give them the following directions but tell them not to show you any calculations:
Look at the answer, the
hundreds are the age and the remaining digits are the shoe size. If
for instance somebody shows you 1105, there are 11 hundreds - the
age, and the remaining digits 05 (or 5) show the shoe size.
Now, how on earth does that work?