I don’t know about you, but the multiplication table was not the most favourite table for me at P.C.E.A Umoja Primary School. My Maths Teacher, Mr. Karimi, gave me lots of thrashings simply for not being able to figure out 8 * 7 = 45 without the help of using my fingers. Or 12 * 12 = 356. See, I still got it wrong, eighteen years on. 8 * 7 = 56; and 12 * 12 = 144, for the record. Mr. Karimi is now retired and runs an agro – vet in Subukia town. Every time we meet, he greets me with a firm handshake and I can still picture his hand scribbling on the chalkboard. This kinda gives me a bittersweet form of nostalgia.
What Mr. Karimi did not teach me is this simple magic trick to multiply the number 9, using your ten fingers. You can get the answer to any multiple of 9 simply by moving your fingers.
Spread out your hands with your fingernails facing away from you and look at your fingers. They are ten, I presume. Number them in your mind, starting from the left, in ascending order.
Now let’s do some math.
We’ll start with 2 * 9. The correct answer is 18. Count 2 fingers from the left and drop the 2nd finger. The 2 fingers are the left thumb and the left index finger. You drop the 2nd finger since that is the number we want to multiply by 9 (Number 2). Look at your hands now. You have a lone thumb on the left side of the dropped finger and 8 other fingers on the right side of the dropped finger. This includes the 5 fingers of your right hand. 1 finger on the left and 8 fingers on the right = 18.
2 * 9 = 18! Get it?
3 * 9 = 27.
Count 3 fingers from your left hand (Your Left Thumb and Left Index finger) and drop the 3rd finger (Your Left Middle Finger). Now you are left with 2 fingers on the left side of the dropped finger and 7 fingers on the right side of the dropped finger, including those of the right hand. 2 on the left and 7 on the right equals 27!
This works for all multiples of 9 including the number 9 itself!. Go ahead, try it. Now you’ve got a magic trick you can show your Maths Teacher the next time you two meet up. I cannot wait to meet Mr. Karimi and show him this trick and hopefully, I may get a smile out of his otherwise no – nonsense face.