You know mathematics is not my field at all and I have good idea how to multiply the numbers from 2 to 9 by 9. It's very easy to do! All you need just your hands! Yep! That's all… And now the instruction: if you need to multiply 4 by 9. Count four fingers and fold down the fourth finger. You will see: the 4 x 9= 36 (3 fingers before and 6 after)). Try to do the trick! It works!