Are you or your students struggling with the (nine) 9 times math table?
When it comes to math, knowing your times table is one of the most important parts of being able to do math problems.
With these simple tricks you and your students won't have any problems with it anymore. You will be able to answer quickly and correctly without even really thinking about the answer or using the very smart method with the fingers.
Although the method is very easy to understand, you may have to explain it to your students a few times before they get it, but when they understand the method, they will think the 9 times table is easier than the 10 times table. My son (when he was 12) worked out this method himself and explained it to me (who never could get the nine times table)
Let's look at counting in nines first:
- When counting in nines, the basic rule is - plus 1 in front and minus 1 at the back
- for example 9 - the number in front of only 9 is actually 0, so 0 + 1 = 1 (this is then the number in front)
- for the number at the back it is 9 - 1 = 8 - so the number in front is 1 and at the back 8, which is 18
- let's go up from there 18 - plus 1 in front (1 + 1= 2) and minus 1 at back (8 - 1= 7) answer = 27
- Let's go a bit higher, just to show you it still works - count in nines from 45
- (plus 1 in front = 5, minus 1 at back = 4 so the answer is 54)
- let's try 72 (plus 1 front = 8 minus 1 back = 1 that gives you 81) you can check it with a calculator if you wish, just to make sure I'm right.
- I'm sure you get this now, so let's move on to how you can do a sum with the 9 x table
With these simple tricks, you can answer the 9 times table quickly:
- Let's look at a small one first 3 x 9
- for the number in front - you take the number that is timed with 9 and minus 1
- In this case it is 3 (minus 1 = 2) so 2 will be in front
- for the number at the back - you say 10 minus that number
- In this case it will be 10 - 3 = 7
- So your answer will be 27
- Let's take another one just to make sure
- 6 x 9
- front 6 - 1 = 5
- back 10 - 6 = 4
- the answer 54 (once again, you can check it with your calculator just to make sure)
- just for good practice, let's take another one
- 8 x 9
- front 8 - 1 = 7
- back 10 - 8 = 2
- answer 72
The downside to this method is that it only works up until 10 times, so for 11 times (which is easy) and 12 times, you and your students will have to know the answer.
Stay tuned, next week I will share with you the secret to doing the 6 times table (which is a little more difficult - can you believe) Before these simple tricks to make the 9 times table so easy, I thought it was the most difficult times table to do.
Do you have any tricks about any of the times tables to make them easier for us? Don't be afraid to share them, we welcome any new learning methods with open arms.
Did you know about this method, because my son figured this out himself, it would be interesting to know if there is someone else who knows this too?
In honor of my son who is so smart in math, I ask you PLEASE DON'T GIVE YOURSELF CREDIT FOR FINDING OUT THIS METHOD, RATHER SEND YOUR FRIENDS TO MY SITE SO THAT THEY CAN SEE IT HERE!!
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