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AAAAAUUUUUUUUGGGGGHHH!!!!Huh, I didn't know this is a thing.
I've pretty much always done math problems in little chunks, and then put all the pieces together afterwards, because my suckage at math cannot be expressed without exponential notation.
In crayon.
Also, interesting to note that Joss Whedon has a Facebook page. Thanks, Freehold DM!
Wow THANK YOU FREEHOLD!
I was doing multiplication and division like this every since I was taught that a*(b+c)=ab+ac. It isn't new math, it's just applied algebra.
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Tensor is right. Cross-multiplication applies to fractions and proportions (also vectors).
The four methods that have been taught for multiplication of multi-digit numbers are (1) the partial products method, (2) the lattice method, (3) the short method (the traditional method), and (4) the Egyptian method.
Everyday Math, a series developed in Chicago, which came out around 2003, encouraged a return to partial products. Why? Because it became obvious, that students were having trouble with our standard division method and most teachers were beginning to experiment with the partial products method of division. So it made sense to change the way we multiply also.
I wonder which method is used in Golarion. Probably the Osirion method.
Ogay, so I'm mistakenly calling the short method "cross multiplying."
Wow THANK YOU FREEHOLD!AAAAAUUUUUUUUGGGGGHHH!!!!Huh, I didn't know this is a thing.
I've pretty much always done math problems in little chunks, and then put all the pieces together afterwards, because my suckage at math cannot be expressed without exponential notation.
In crayon.
Also, interesting to note that Joss Whedon has a Facebook page. Thanks, Freehold DM!
Shiny!
Well when I type Eight Million, Eight Thousand, One Hundred and Thirty Five it makes a hilarious word when I hold it upside down. Does that count?I ALWAYS HAVE A CALCULATOR DAMMIT!Can your calculator proof conjectures? ;-P
SEIBOOB?
Son't you mean 5318008?
7734 works, too, as does 0,7734.
Can we please all agree to call it Maths, and not Math? Remember who invented it!
Or perhaps less jingoistically, remember who didn't invent the word Mathematics :-)
Ok, so this whole post is jingoistic. I can accept that.
Can we please all agree to call it Maths, and not Math?
Nope.
Fair enough.
Is Partial product method anything like the Rhythm Method?
Can we please all agree to call it Maths, and not Math? Remember who invented it!
Or perhaps less jingoistically, remember who didn't invent the word Mathematics :-)
Ok, so this whole post is jingoistic. I can accept that.
I find it funny Americans are all keen to add the redundant s to Lego and Sport but drop it off Maths...
Can we please all agree to call it Maths, and not Math? Remember who invented it!
Or perhaps less jingoistically, remember who didn't invent the word Mathematics :-)
Ok, so this whole post is jingoistic. I can accept that.
I find it funny Americans are all keen to add the redundant s to Lego and Sport but drop it off Maths...
You forgot Ninja.
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Can we please all agree to call it Maths, and not Math? Remember who invented it!
Or perhaps less jingoistically, remember who didn't invent the word Mathematics :-)
Ok, so this whole post is jingoistic. I can accept that.
I find it funny Americans are all keen to add the redundant s to Lego and Sport but drop it off Maths...
I'm a f#*+ing weirdo. Legos, sports, maths... I just love that letter S.
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You forgot Ninja.Can we please all agree to call it Maths, and not Math? Remember who invented it!
Or perhaps less jingoistically, remember who didn't invent the word Mathematics :-)
Ok, so this whole post is jingoistic. I can accept that.
I find it funny Americans are all keen to add the redundant s to Lego and Sport but drop it off Maths...
Or would that be ninjas???
Why? What's wrong with the old way?You can do partial products in your head waaay faster than the old way. But the old way still works.
I can do most 3 digit * 3 digit in my head in about 10 seconds.
Funny, the partial method is the only way I knew about, which means that's the one I learned at school somewhere in early '80s. I'm pretty sure that's how my European friends of my generation learned it too (at least in France and Germany).
It can't be that new...
Same way we learned it in Sweden in the mid-to-late 80s. And for that matter, it's the way my parents solve multiplication and division too. So yeah, not very new.
Just out of curiosity, how did the "old" method look?
.
.
.
.
.
4
3
.. 28
x 54
------
. 112
1400
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1512
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Here's an example of both methods: Suppose you need to solve 83 x 27.
Using partial products, you think: 80 x 20 is 1600, 80 x 7 is 560, 3 x 20 is 60, and 3 x 7 is 21. Then you add those partial products to get 2241.
The traditional method goes like this: 7 x 3 is 21, carry the 2, 7 x 8 is 56, add the carried 2 is 58. So the number 581 is written under the problem. Then move over one digit (or put a 0 in the ones place of the second product) and 2 x 3 is 6, 2 x 8 is 16. Add: 581 + 1660 = 2241.
The partial products method preserves place value every step of the way, while the traditional method requires children to line up the problem carefully. So by teaching the partial product method, teachers are instilling number sense; in other words, attaching meaning to the numbers.