I do that when I’m computing large numbers. It does make it easier at times to do that, so it’s not totally worthless.
However, it’s probably too early to introduce that sort of mathematical principle. You can’t teach algebraic principles to,kids who are still learning basic math.
I used skip math...
7 + 7 = 1+1+1+1+1+1+1+1+1+1+1+1+1+1=10 fingers + 4 toes
https://www.youtube.com/watch?v=wIWaJ0sy03g
No comment necessary, other than this was from the ‘60s.
Number bonds?
Looks like one of my chemistry problems from high school.
E = 1/2 mv^2 /7000 * 32.163
I have always used these types of methods when doing math. I can generally add 4 digit numbers together in my head, and multiply 2 digit numbers together in my head, accurately.
I remember in the 5th grade, I went to a math contest, and they had something called ‘ciphering’. They would flash a problem on a screen, and you had a few seconds to write an answer down - deliberately so quick it had to be done in your head. I won the event.
And I’ve spent my entire life doing math every day at my job (engineer). So this is a very good method.
Having said that - it is most definitely not a method that most kids can use. Throughout the years I have tried to explain how to do math in your head quickly...only people who are already real good at math can do it. I don’t think they should be teaching this at all.
How many fingers do you see Winston?
I suppose I could see 4, but yes, yes, I see how there could be 5.
How many fingers do you see Winston?
How many do you want me to see?
I pity the Children. I’m glad I never had any of my own.
7 + 7 = 7 + (3 + 4)
= (7 + 3) + 4
= 10 + 4
= 14
What I don't get is, why? I don't see what value is added to teaching arithmetic. It's a lot simpler, isn't it, to just explain why you have to carry a one into the tens column. Maybe I'm missing something?
I learned this week that my third-grade teacher has passed away. It was in her class that we learned to add multiple columns, and also memorized our multiplication tables up to 12x12.