I’ve peripherally heard of some New Math that’s being taught in schools for the last couple of years that is different from the way I learned. When I do math I start with the right side and work my way over to the left but the New Math apparently works over from the right to left.
So for example where I did math like this:
1
19 19
+11 +11
=== ====
30
Now my question is this: how does the new math work? I mean, if there’s no 1 carrying (since its starting with the 10 integer and working over to the right), does it add another row underneath like so:
19 19 19
+11 +11 +11
=== === ===
2 20
10
===
30
If anybody knows, can you let me know? My son has reached a point with math that we need to address this but we want to make sure we have the method right so that when the teachers try to indoctrinate, he already has their methodology down.
Thanks in advance.
5 Comments
I learned to add this way when I had a job that required a lot of adding. It does allow you to calculate in your head a lot faster.
I would run down to your library and check out a book called “math magic” by Scott Flansburg. (Page 11 http://tinyurl.com/2ltts2 ) I think it is good for you brain, and it definately allows you to add faster once you get the hang of it.
I would think of it more as 10+10 =20, 1+9=10, 10+20=30
I also liked the HP reverse Polish Calculators, which allowed you to keep stacks of numbers in memory like that.
Dude, that is excellent: Thanks for the book recommendation!
Completely unrelated comment but this is awesome:
http://www.fingertoe.com/2008/03/what-is-twitter.html
This depresses me. Not the basic concept; Josh R’s “10+10 =20, 1+9=10, 10+20=30″ breakdown made it very clear, and it does seem faster than carrying 1′s. But I remember distinctly by 1st or 2nd grade losing the illusion that my parents were omniscient geniuses when they couldn’t help me with my math homework. By the time I have kids, it’s not going to matter that I had a 99% math average in high school; what I know will be so outdated I’m going to seem like a moron.
I think I need to ask my parents what their grades were like when they were in school, then apologize.
We’re old enough that kids are learning differently; let our obsolescence begin….
Right-to-left will always be the right way to add on paper, but when I add in my head, I do it left-to-right. Always have. It requires less RAM.