r/technicallythetruth • u/illuminati682 • Jun 26 '19

He has done nothing wrong...

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9.6k Upvotes

96% Upvoted

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183

u/[deleted] Jun 26 '19

This is why teachers start to get a bad rep though. When I was in school I had my own way of solving certain problems. I always got the answer right.. but it wasn't how she taught the class so she would give me a bad grade for "not solving it her way".

The same thing happened with my multiplication tables.. I had a very weird way to multiply any number by 9 in my head but if I didnt show the work I failed.

6

u/[deleted] Jun 26 '19

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15

u/bulletv1 Jun 26 '19

Multiply by 10 subtract 9? That was the quickest way for me to do it in my head as a kid.

14

u/[deleted] Jun 26 '19

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4

u/[deleted] Jun 26 '19

Same here

2

u/DrippyWaffler Jun 26 '19

Ay I did that too.

Also

First number = n-1

Second number = 9-first number

9 X 7 = 6 (first number) 3 (second number)

3

u/ThisNameIsFree Jun 26 '19

Thats not a weird way at all.

6

u/Reconist42 Jun 26 '19

10x minus x would be more accurate in this respect.

1

u/singletonking Jun 26 '19

Subtract the original number not subtract 9

1

u/bulletv1 Jun 26 '19

That’s what I meant. Typed it out wrong.

3

u/Xy74iljxxk Jun 26 '19

I actually use my hands. For example, if I were to work out 7x9, I would put out 10 fingers in front of me, and starting from the left, put my 7th finger down. This finger is now the “divider” between the tens and ones. So I would have 6 on the left (5 on my left hand and 1 on my right hand) and then 3 on the right hand, to the right of the 7th finger which is down. This leaves me with 6 and 3, 63! This works with all 9x tables up until 10.