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 03-01-10, 08:50 PM #1 RubenX  Look! My Spine! Thread Starter     Join Date: Apr 2008 Location: Kissimmee, FL Bikes: Posts: 620 Mentioned: 0 Post(s) Tagged: 0 Thread(s) Quoted: 2 Post(s) Left to Right addition SUCKS! Who the heck came up with this idea? And how the heck are parents supposed to help their children with math homework if they are now told to add in this totally weird alien way? SUCKS SUCKS SUCKS! And that's it
 03-01-10, 08:56 PM #2 StupidlyBrave  Chepooka     Join Date: Sep 2006 Location: South Central PA Bikes: 1990 Trek 1400 7spd; 2001 Litespeed Arenberg 10 speed Posts: 1,168 Mentioned: 0 Post(s) Tagged: 0 Thread(s) Quoted: 64 Post(s) Aliens have really fast spaceships. So don't knock it until you've tried it Seriously though. This is just arithmetic, right? It's the same either way.
03-01-10, 09:03 PM   #3
RubenX
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 Originally Posted by StupidlyBrave Aliens have really fast spaceships. So don't knock it until you've tried it Seriously though. This is just arithmetic, right? It's the same either way.
No is not!

see back in the 70's where it was simple:

19
+11
-----

We use to start on the right, adding 9 +1 which gave us 10... place the 0 down there, get the 1 on top of the next column, then add the three 1's which is 3 and put the the 3 down there .... voila! = 30

But the other way around, 1 + 1 = 2, then you move to 9 + 1 = 10 and that makes my boy end up with fricking 210 as a result. *me nods*

And because I have no idea what the heck he's thinking, I'm having a lot of trouble pinpointing where he's getting it wrong. Google pointed me to this... arg.. this sucks

PS: oh, and my girl ate ALL my fricking cookies... all of them! didn't left a single one for me

 03-01-10, 09:11 PM #4 Tom Stormcrowe Out fishing with Annie on his lap, a cigar in one hand and a ginger ale in the other, watching the sunset.     Join Date: Mar 2006 Location: South Florida Bikes: Techna Wheelchair and a Sun EZ 3 Recumbent Trike Posts: 16,128 Mentioned: 0 Post(s) Tagged: 0 Thread(s) Quoted: 0 Post(s) It's like using a slide rule is all (Kinda). __________________ . “He who fights with monsters might take care lest he thereby become a monster. And if you gaze for long into an abyss, the abyss gazes also into you.”- Fredrick Nietzsche "We can judge the heart of a man by his treatment of animals." - Immanuel Kant
 03-01-10, 09:19 PM #5 StupidlyBrave  Chepooka     Join Date: Sep 2006 Location: South Central PA Bikes: 1990 Trek 1400 7spd; 2001 Litespeed Arenberg 10 speed Posts: 1,168 Mentioned: 0 Post(s) Tagged: 0 Thread(s) Quoted: 64 Post(s) Kids today don't have the benefit of lead in their paint chips like we did back then. We learned that way through endless repetition. I assume that your son's addition section was immediately preceded by problems involving estimation. I also assume he'll have a lot more of these. The point is, that he is supposed to recognize the significance of the place value (i.e. it's ten not one). That is precisely the advantage that the link you provided cites. It's probably better to stick to one methodology than confuse him by introducing another. BTW, I learned to read in ita. Look where that went .
03-01-10, 09:21 PM   #6
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 Originally Posted by RubenX No is not! see back in the 70's where it was simple: 19 +11 ----- We use to start on the right, adding 9 +1 which gave us 10... place the 0 down there, get the 1 on top of the next column, then add the three 1's which is 3 and put the the 3 down there .... voila! = 30 But the other way around, 1 + 1 = 2, then you move to 9 + 1 = 10 and that makes my boy end up with fricking 210 as a result. *me nods* And because I have no idea what the heck he's thinking, I'm having a lot of trouble pinpointing where he's getting it wrong. Google pointed me to this... arg.. this sucks PS: oh, and my girl ate ALL my fricking cookies... all of them! didn't left a single one for me
The error is in saying that 1 + 1 is 2. You are breaking apart the numbers into tens and ones and combining. It is really adding 10 + 10 and 9 +1 and combining those two sums. So 10 + 10 is 20 and 9 +1 is 10, now add 20 and 10 together to get a sum of 30. This method is meant to preserve place value in addition.
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03-01-10, 09:25 PM   #7
GP
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 Originally Posted by <3 2 Ride The error is in saying that 1 + 1 is 2. You are breaking apart the numbers into tens and ones and combining. It is really adding 10 + 10 and 9 +1 and combining those two sums. So 10 + 10 is 20 and 9 +1 is 10, now add 20 and 10 together to get a sum of 30. This method is meant to preserve place value in addition.
1+1 doesn't equal 2? No wonder it took me 4 years to get to second grade.

03-01-10, 09:29 PM   #8
RubenX
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 Originally Posted by <3 2 Ride The error is in saying that 1 + 1 is 2. You are breaking apart the numbers into tens and ones and combining. It is really adding 10 + 10 and 9 +1 and combining those two sums. So 10 + 10 is 20 and 9 +1 is 10, now add 20 and 10 together to get a sum of 30. This method is meant to preserve place value in addition.
You are a teacher aren't you?

03-01-10, 09:29 PM   #9
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 Originally Posted by GP 1+1 doesn't equal 2? No wonder it took me 4 years to get to second grade.
Man I love Foo.

1 + 1 = 2 when you are talking about numbers with a place value of one. However, when you are talking about numbers with a place value of ten, 1 + 1 is really 10 +10. I would guess that place value is why it took you 4 years to get to second grade.
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03-01-10, 09:30 PM   #10
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 Originally Posted by RubenX You are a teacher aren't you?
She's the hot teacher...

03-01-10, 09:37 PM   #11
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 Originally Posted by UnsafeAlpine She's the hot teacher...
Oh woah woah, I'm hot for teacher!
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 03-01-10, 09:41 PM #12 JoelS Senior Member   Join Date: Jun 2008 Location: Near Sacramento Bikes: Posts: 4,890 Mentioned: 0 Post(s) Tagged: 0 Thread(s) Quoted: 2 Post(s) 1+1=10 in binary __________________ ------- Some sort of pithy irrelevant one-liner should go here.
03-01-10, 09:47 PM   #13
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 Originally Posted by JoelS 1+1=10 in binary
Great... now I also need to teach the boy about transistors, logic gates, flip flops, carnaugh maps, circuit states, 8-bit assembly.....

 03-01-10, 09:52 PM #14 Connell Wheezy Rider     Join Date: Jul 2009 Location: 8,750' Bikes: Posts: 280 Mentioned: 0 Post(s) Tagged: 0 Thread(s) Quoted: 0 Post(s) Calvin explains it all here. http://www.grymonpre.com/math/chmath.htm
03-01-10, 10:01 PM   #15
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 Originally Posted by Connell Calvin explains it all here. http://www.grymonpre.com/math/chmath.htm
lol... that's win

03-01-10, 10:18 PM   #16
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 Originally Posted by RubenX Who the heck came up with this idea? And how the heck are parents supposed to help their children with math homework if they are now told to add in this totally weird alien way? SUCKS SUCKS SUCKS! And that's it
Just rearrange it to do the calculations... what's the big deal how it's presented on paper?

4+6+5+3+2+7=? is no different than:

4
6
5
3
2
+7
------
?

Can you not do the transposition, then take the answer and put it on the right side of the left to right equation??

03-01-10, 10:28 PM   #17
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 Originally Posted by skiahh Just rearrange it to do the calculations... what's the big deal how it's presented on paper? 4+6+5+3+2+7=? is no different than: 4 6 5 3 2 +7 ------ ? Can you not do the transposition, then take the answer and put it on the right side of the left to right equation??
Adding a line of single digits, yeah, but the some of 465 + 327 = ? is easier to visualize as 465
.................................................................................................... ................................+ 327
.................................................................................................... .................................-------

 03-02-10, 12:14 AM #18 CliftonGK1 Senior Member     Join Date: Jul 2006 Location: Columbus, OH Bikes: '08 Surly Cross-Check, 2011 Redline Conquest Pro, 2012 Spesh FSR Comp EVO, 2015 Trek Domane 6.2 disc Posts: 11,378 Mentioned: 0 Post(s) Tagged: 0 Thread(s) Quoted: 1 Post(s) The "new math" is all well and good until the kids hit college, and professors expect everyone to understand and utilize the "old school" methodology. __________________ "I feel like my world was classier before I found cyclocross." - Mandi M.
03-02-10, 06:12 AM   #19
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 Originally Posted by JoelS 1+1=10 in binary
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03-02-10, 06:29 AM   #20
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 Originally Posted by ModoVincere wuss.....what's it in hexadecimal?
MSsxPTI=

(Base 64 for 1+1=2)

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03-02-10, 06:35 AM   #21
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 Originally Posted by Tom Stormcrowe MSsxPTI= (Base 64 for 1+1=2) Hexadecimal is for woosy.
I is wussy then, cause that reads like greek.
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03-02-10, 06:46 AM   #22
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think MIMEencoding
Quote:
 Originally Posted by ModoVincere I is wussy then, cause that reads like greek.
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 03-02-10, 06:49 AM #23 Metzinger Primate     Join Date: Jan 2006 Location: gone Bikes: Concorde Columbus SL, Rocky Mountain Edge, Sparta stadfiets Posts: 2,582 Mentioned: 0 Post(s) Tagged: 0 Thread(s) Quoted: 0 Post(s) I was taught short division in grade 4. Got called on it in junior high by a marker who wanted to see my work. Then I had to get up in front of the whole class and demonstrate it on the blackboard. People were looking at me like I was an alien. I still wake up screaming.
 03-02-10, 08:00 AM #24 RubenX  Look! My Spine! Thread Starter     Join Date: Apr 2008 Location: Kissimmee, FL Bikes: Posts: 620 Mentioned: 0 Post(s) Tagged: 0 Thread(s) Quoted: 2 Post(s) Gee, I don't even remember what the heck I was doing in 4th grade. I only remember the school I went to and the girl I liked.
 03-02-10, 08:06 AM #25 apricissimus  L T X B O M P F A N S R     Join Date: Jun 2008 Location: Malden, MA Bikes: Bianchi Volpe, Bianchi San Jose, Redline 925 Posts: 2,334 Mentioned: 2 Post(s) Tagged: 0 Thread(s) Quoted: 1638 Post(s) I think it's a good idea to teach several different ways to add. Or multiply, or whatever. In my head I add 19 and 11 like this: Take 1 from 11 and add it to 19 to get 20. Since you took the 1 from 11, it's 10 now. So add 10 to 20 to get 30. Emphasizing just one method makes it seem like a recipe, or just a typographical trick. Introducing different methods increases the chances that one of them will click with a student, and they'll see what's really going on. And teaching different methods encourages kids to use different mental models to do mathematics, a very useful skill.