This mathematrick is so easy to understand you’ll know your 9 times tables like the back of your hand (sorry).
To multiple any number between 1 and 9 by 9, hold both hands in front of your face . Next, drop the finger that corresponds to the number you are multiplying. Eg, If you’re multiplying 9 by 3, you’d drop your third finger.
Now count the fingers before the dropped finger (with our example this will be two fingers).
Finally, count the numbers after the dropped finger (seven in this example).
Put the two numbers together, and hey presto!
There’s your answer. 27.