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Struggling with the nine times table? I have a failsafe method (www.theguardian.com)
submitted 4 months ago by to c/nottheonion@lemmy.world
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Apparently, nines are the hardest to grasp for primary school children. If only they’d learned how to cheat like me, says Adrian Chiles

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[–] 9 points 4 months ago (4 children)

10x8 is 80. Minus 8. Is 72.

That's how I do it. I actually struggle a lot with 7x and 8x.

Still don't know 6x7 7x8 8x8 8x6

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  • [–] 2 points 4 months ago (1 child)

    1-9 by 9 is easy though.

    Take the first number, subtract 1 from it, and that will be your 10's place. Your 1's place with be whatever that first number needs added to it to get to nine.

    Example... 7x9. 7-1= 6, so 60. 9-6=3. Answer is 63.

    Another fun math trick while we're at it. If you want to know if a number is divisible by 3, just add up all the digits, and if that number is divisible by 3, then so is your original number. 3135...3+1+3+5=12, so 3135 is divisible by 3.

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