Murderous Maths
The 1089 Trick

This trick has two "magic" stages.

  • Write down a three digit number, the digits must be different and the biggest digit must be at the front.
  • Reverse the number and write it underneath. (The middle digit should stay in the middle.)
  • Subtract the lower from the higher. (If you get "99" put a zero in front to make "099")
  • First bit of "magic": your answer will have "9" in the middle. Also the first and last digits will add up to 9.
  • Reverse this answer.
  • Add the last two answers.
  • Second bit of "magic": the total is... 1089
Example a:






Example b:






This trick and many others are explained in the book The PHANTOM X (algebra)

1089 FACTS

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