Use Your Fingers To Do The 9s Times Tables
The multiplication tables are a foundational element of mathematics, and for many, the 9s times table can feel like a particularmente tricky hurdle. While rote memorization is a common approach, it often leads to frustration and a lack of genuine understanding. However, there’s a surprisingly simple and elegant trick that allows you to use your fingers to do the 9s times tables with remarkable ease and accuracy. This method not only helps you recall the answers instantly but also provides a visual and kinesthetic way to grasp the pattern inherent in multiplying by nine.
Forget the endless drilling and the fear of getting it wrong. This finger trick transforms learning the 9s multiplication into an engaging and almost game-like experience. It’s perfect for students struggling with memorization, for parents looking for a fun way to help their children, or even for adults wanting a quick mental refresh. All you need are your ten fingers, and a little bit of visual understanding.
Unveiling the Magic: The Ten Finger Method
The core of this ingenious method lies in assigning each finger a number from one to ten, starting with your left pinky as one and ending with your right pinky as ten. Imagine your hands laid out flat in front of you.
Left Hand:
Pinky: 1
Ring Finger: 2
Middle Finger: 3
Index Finger: 4
Thumb: 5
Right Hand:
Thumb: 6
Index Finger: 7
Middle Finger: 8
Ring Finger: 9
Pinky: 10
Now, to find the answer to any multiplication problem involving nine, from 9 x 1 all the way up to 9 x 10, you simply fold down the finger corresponding to the number you are multiplying by. The fingers to the left of the folded-down finger represent the tens digit of your answer, and the fingers to the right represent the ones digit.
Let’s try an example to illustrate. Imagine you want to calculate 9 x 3.
1. Identify the multiplier: You are multiplying by 3.
2. Locate the corresponding finger: On your left hand, your middle finger represents the number 3.
3. Fold down the finger: Bend down your left middle finger.
4. Count the fingers:
Fingers to the left of the folded finger (your left pinky and ring finger) represent the tens. That’s 2 fingers. So, your tens digit is 2.
Fingers to the right of the folded finger (your left thumb, and all fingers on your right hand) represent the ones. That’s 1 finger on the left hand and 5 fingers on the right hand, totaling 6 fingers. So, your ones digit is 6.
Putting it together, the answer to 9 x 3 is 26.
Practicing the 9s Times Tables With Your Fingers
Let’s explore a few more examples to solidify your understanding and build your confidence in using your fingers for multiplication.
9 x 7: A Deep Dive
To calculate 9 x 7:
1. Multiplier: 7.
2. Corresponding finger: On your right hand, your index finger represents the number 7.
3. Fold down the finger: Bend down your right index finger.
4. Count:
Fingers to the left of the folded finger: This includes your left hand (5 fingers) and your right thumb (1 finger). That’s a total of 5 + 1 = 6 fingers. The tens digit is 6.
Fingers to the right of the folded finger: These are the fingers on your right hand to the right of your index finger – your right middle finger, ring finger, and pinky. That’s 3 fingers. The ones digit is 3.
Therefore, 9 x 7 = 63.
9 x 10: The Final Frontier
To calculate 9 x 10:
1. Multiplier: 10.
2. Corresponding finger: Your right pinky represents the number 10.
3. Fold down the finger: Bend down your right pinky.
4. Count:
Fingers to the left of the folded finger: All fingers on your left hand (5) and all fingers on your right hand except the pinky (4). That’s 5 + 4 = 9 fingers. The tens digit is 9.
Fingers to the right of the folded finger: There are no fingers to the right of your folded right pinky. The ones digit is 0.
So, 9 x 10 = 90.
9 x 1: The Beginning
To calculate 9 x 1:
1. Multiplier: 1.
2. Corresponding finger: Your left pinky represents the number 1.
3. Fold down the finger: Bend down your left pinky.
4. Count:
Fingers to the left of the folded finger: There are no fingers to the left of your folded left pinky. The tens digit is 0.
Fingers to the right of the folded finger: All other nine fingers are extended. The ones digit is 9.
Thus, 9 x 1 = 09, which is simply 9.
The Underlying Pattern Explained
This finger trick works because of a fascinating pattern related to the digits of the multiples of nine. For any multiple of nine, the sum of its digits always equals nine. For example:
9 x 1 = 09 (0 + 9 = 9)
9 x 2 = 18 (1 + 8 = 9)
9 x 3 = 27 (2 + 7 = 9)
9 x 4 = 36 (3 + 6 = 9)
9 x 5 = 45 (4 + 5 = 9)
9 x 6 = 54 (5 + 4 = 9)
9 x 7 = 63 (6 + 3 = 9)
9 x 8 = 72 (7 + 2 = 9)
9 x 9 = 81 (8 + 1 = 9)
9 x 10 = 90 (9 + 0 = 9)
When you fold down a finger, you are essentially dividing the numbers from 0 to 9 (representing the tens and ones digits) into two groups. The number of fingers to the left of the folded digit directly corresponds to the tens digit, and the number of fingers to the right corresponds to the ones digit. Because the total sum of the digits for any multiple of nine is always nine, the number of fingers to the left and the number of fingers to the right will always add up to nine, perfectly mirroring this mathematical property.
Beyond Memorization: A Deeper Understanding
The beauty of the “Use Your Fingers To Do The 9s Times Tables” trick is that it transcends simple memorization. It provides a tangible, visual, and kinesthetic learning experience. For children, it transforms a potentially daunting task into an enjoyable activity. For adults, it’s a delightful way to recall facts quickly and impress others with a clever mental shortcut. Mastering this technique not only equips you with the ability to solve 9s multiplication problems effortlessly but also fosters a deeper appreciation for the logic and patterns within mathematics. So, go ahead, try it out – you might be surprised at how quickly you become a 9s times table whiz!