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One of the guys at work was talking about this the other day. They are teaching his 6 year old to do math this way. Seems messed up. But with large numbers that is exactly how I do it in my head. There are probably better ways to do it though.
All in all, seems really messed up to me.
Jack of all trades, master of none, though often times better than master of one.
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John Simmons / outlaw programmer wrote: I understand how they got there, but I DON'T understand how that's a better way to do it. 
Maybe it's because a minus sign promotes negative thoughts about math...
Side stepping my "Why is there an S added to Lego but missing from Maths rant"
And just wait until they move on into programmer roles in the future. Just imagine the length and breadth of their algorithms and functions to accomodate their Common Core stuff.
Luckily you'll be retired by then, I hope I am too or at least in another industry.
Michael Martin
Australia
"I controlled my laughter and simple said "No,I am very busy,so I can't write any code for you". The moment they heard this all the smiling face turned into a sad looking face and one of them farted. So I had to leave the place as soon as possible."
- Mr.Prakash One Fine Saturday. 24/04/2004
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Common sense says: If it ain't broke, don't fix it.
That's what we got here: failure to apply common sense.
"Old" style mathematics got a couple of guys on the moon, lots of stuff in space and all these computers/devices we like so much. That means at least some of the old style calculations got it right.
Change for the sake of change is just plain stupid.
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Filip Dossche wrote: If it ain't broke, don't fix it.
You have seen the educational levels of the average American right?
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I'm in the US and luckily they are not doing that where I live.
There are only 10 types of people in the world, those who understand binary and those who don't.
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It is determined largely by partisan political motivations. To keep it lounge-safe, I'll just say that where you are is a different political side than the national political side that is giving/taking money from local political bodies for accepting or rejecting this political agenda.
There... I didn't argue about politics.
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I think the idea is to move from the lower number to the larger number in small steps that are each easy to do:
3 + 5 = 8,
8 + 10 = 18,
18 + 2 = 20
Yay! There is the answer!
The old way way was obviously way too complicated where you have to do:
The "ones" column: 2 - 2 = 0
The "tens" column: 3 - 1 = 2
...and then you wrote the "tens" answer followed by the "ones" answer to get 20
Yay! There is the answer!
Of course, you could make it even easier by only incrementing the lower number by 1 until you reached the larger number and then counting how many times you had to do that. 20 Yes! That should be the new method! Much simpler!
Or, for future programmers using nice round, easily remembered numbers:
12 + 4 = 16
16 + 8 = 24
24 + 8 = 32
____
20
- I would love to change the world, but they won’t give me the source code.
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Quote: Of course, you could make it even easier by only incrementing the lower number by 1 until you reached the larger number
You can borrow my fingers if you need to. 
There are only 10 types of people in the world, those who understand binary and those who don't.
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Quote: You can borrow my fingers if you need to
No thanks; I hate to think where they might have been!
- I would love to change the world, but they won’t give me the source code.
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I'm flattered to be in your dreams but really, this has got to stop.
There are only 10 types of people in the world, those who understand binary and those who don't.
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Dreams, dreams? Now the nightmares begin...
 
- I would love to change the world, but they won’t give me the source code.
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My son's going through this now and it's driving my wife crazy. I've reviewed it and I think I understand the "why" behind it. I've started thinking I look at numbers differently than her. Most Americans learn math by memorization - flash cards, repetitive tables, etc. They don't think about what the numbers actually mean. They are stuck as they have only memorized base 10.
What happens when you need to understand base 2, 8, 16, 535? The majority of Americans can't figure those out. They never had flash cards for that. However, this is teaching kids early how to understand the value of the number outside of what they have memorized.
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Now I don't mean to defend this nonsense. Understanding how to subtract properly is clearly important and the 'count up in increments' method is generally longer and therefore more error prone. However, this is how people often count out change ("that's £6.52, sir" ... *hands over tenner* ... "and your change ... six fifty two, six sixty, seven, eight, ten" as he hands me the 8p, a 10p, two 20s, two £1s and a £2) and it may be a good way in for people who aren't getting it, or want a way to confirm their 'proper' subtraction is working correctly.
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That is well and good for counting UP in money, where you end on a larger denomination of base 10.
But how will common core work on fractions and algebra/calculus, etc where you have to determine multiple variables, which may or may not be easily expressed as a base 10 whole number 
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BobJanova wrote: "that's £6.52, sir" ... *hands over tenner* ... "and your change ... six fifty two, six sixty, seven, eight, ten" as he hands me the 8p, a 10p, two 20s, two £1s and a £2
So you score £1.20? I can see the value in this method. 
What is this talk of release? I do not release software. My software escapes leaving a bloody trail of designers and quality assurance people in its wake.
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No, he only scores £1.10. £0.08 + £0.10 + £0.20 + £0.20 + £1.0 + £1.0 + £2.0 = £4.58
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Skitt's Law strikes again. 
What is this talk of release? I do not release software. My software escapes leaving a bloody trail of designers and quality assurance people in its wake.
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I knew I should have checked that more carefully ...
The counting out is correct, the coinage isn't. Should be 8p, 2x20p, £1, £2 obviously.
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I haven't had anyone count out change since the mid 80's.
".45 ACP - because shooting twice is just silly" - JSOP, 2010
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You can never have too much ammo - unless you're swimming, or on fire. - JSOP, 2010
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When you pry the gun from my cold dead hands, be careful - the barrel will be very hot. - JSOP, 2013
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Still happens moderately often on market stalls, I find, and in some independent shops too.
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I am not sure how this is better way. If someone claims this is helpful in real World calculations, I do not get how. I mean how can it be easy to subtract using 10 steps instead of traditional? If they are really after an alternate way, why not Vedic Maths[^]? I did a beginner course in middle school on it and did find it weird at first. But once I became habitual, it was quick.
As far as this method is concerned, this[^] is what I found.
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I homeschool my kids.
My son is waaaaay ahead of grade level in math. But I don't think he enjoys it and everything is quite tedious. I would like some additional ways of approaching problem solving. I think this may be a nice fit. Thanks for the link to vedic.
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