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#Homeschooling / #unschooling is the way. My seven year old would have likely been diagnosed with ADHD if his "teachers" got their way.

He has gone from illiterate to reading novels, and showing real talent for mathematics. He is completely self taught except when I occasionally show him some fun tricks with numbers like in the picture.

And the most important part is how much happier he is.

#trachtenberg

Rooney 2y ago

I'm surprised they haven't diagnosed every kid with ADHD and started handing out aderol at the door when they walk in. Public schools are just indoctrination camps. And since I went to one for 13 flippin years I can't figure out the trick in your pic. Looks like you are doing multiplication like normal except starting with the front number instead of the second?

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Discussion

Lucas 2y ago

Trachtenberg starts from the right like regular multiplication, but doubles and halves instead of memorising the times tables. Carried numbers are maximum 2 so there is very little room for simple errors.

The rule for 12 is "double each number in turn then add its neighbour". The neighbour is the number to the right.

So 12 x 123456 would be:

Double 6 plus 0 = 12. Keep the 2 and take the 1 to the next number.

Double 5 plus 6, plus the 1 from 12 = 17. Keep the 7 and carry the 1.

Double 4 plus 5, plus carried 1 = 14. Keep 4, carry 1.

Double 3 plus 4, plus the carried 1 = 11. Again carry 1.

Double 2 plus 3, plus the carried 1 = 8.

Double 1 plus 2 = 4.

Finally there's always an invisible "0" at the start of each number. So it's double 0 plus 1 = 1.

Answer: 12 x 123,456 = 1,481,472.

It looks complicated the way I've explained it, but I promise it's not!

Rooney 2y ago

Very nice!