Anybody can learn to count fast if he knows the secret of the following trick.
Ask your friend to write any five-figure number on the blackboard. Then you write your five-figure number under it. You choose your figures so that each one with the figure above it will make nine.
For example: His number: 45 623
Your number: 54 376
Tell your friend to put a third five-figure number under your number. Then you write a fourth number in the same way. After he has written the fifth number, you draw a line under it and quickly write the sum. You may even write it from left to right!
How do you do it? You subtract two from the fifth number and put 2 in front of your answer. For example: if the fifth number is 48 765, the sum will be 248 763.
