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Comment Re: wait, what? (Score 1) 159

"Driver hits unleashed dog that darted into street" is just a Tuesday, but "autonomous vehicle hits^w makes contact with unleashed dog that darted into street" is a headline because it is so rare.

I'm not so sure there have even been enough incidents to decide if Waymos are more or less likely to run over an animal, but I *STRENUOUSLY* object to trying to soften it with 'made contact with' in the press release.

Comment Re:The talented ones can (Score 1) 259

Thus 5x3 becomes 5x5x5 or 3x3x3x3x3 instead of "STFU and memorize your times tables."

I'm fine with the repeated addition. My objection is the OR in your statement. Apparently not. The question was 5x3 and the kid wrote 5+5+5=15 and got marked wrong with no explanation because the teacher wanted 3+3+3+3+3=15. So I guess that you would have had a 50% chance of being marked wrong on a 2nd grade arithmatic worksheet as well, as absurd as that is. Correct answer notwithstanding.

BTW, that's not at all new. We covered multiplication that way in the 3rd grade back in 1975. Memorizing the table was just to make it quicker. I quickly "discovered" the commutative property while looking at the multiplication table and cut my memorization load in half. The part that confused the father was why is 5x3 = 5+5+5=15 "wrong".

As for 37+55, we decomposed that in the '70s as well, but I soon decided the easier decomposition was 37+55= 87+5 = 90+2=92. So I would say that meme was just someone wanting to complain. Of course the "old way" ends up in 30+50+10+2 anyway.

Shut up and memorize was not in practice during the education of the parents of today's students.

Comment Re:The talented ones can (Score 1) 259

It was my example. It came from a photograph of the worksheet posted to Reddit by the child's father, who was wondering why the answer was 'wrong'.

Surely you don't expect the 2nd graders to start on Clifford algebras any time soon. They need to learn to walk before they run. Note that by the time you're multiplying vectors and matrices the process involved is sufficiently different from multiplying real numbers that not being commutative is not going to be an issue. I recall my high school math teacher demonstrating non-commutative multiplication. I was not confused in spite of having figured out the commutative nature of simple multiplication in elementary school.

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