Help me find an algorithm please

[amo_mea_filiis.]

Subtraction with borrowing and regrouping is very messy and dd makes a lot of errors.

 

When i took remedial math in college, the professor introduced me to a wonderfully clean way of subtracting, but she taught it because that was how she learned. We worked on subtraction for maybe 10 minutes during one class.

 

Anyway, it was similar to the Austrian method (that i just found tonight), but the "little ones" were in different places.

 

I have no clue if i can explain this.

 

56

-49

 

Put a little 1 to the top left of the 6 and the bottom left of the 4. So it would be 16-9=7. 5-4-1=0. So the answer is 7.

 

In the Austrian method, the "little ones" go in the middle of the problem and seem a bit more confusing.

 

Anyone have any clue what I'm talking about? I want to find a video to help me explain it to dd.

[Celia]

I do know what you're talking about, but I've no clue where to find a video about it!

 

Could you just do up a worksheet with a lot of sample problems to show your dd?

[amo_mea_filiis.]

I'm not explaining it in a way that makes sense to her.

 

I could just do a ton of problems with her until it sticks. Maybe if she sees it over and over, something will click.

[Dana]

I found that using base 10 blocks for the problem as he wrote the steps (traditional algorithm) was very helpful to my son.

With long division especially, I'd make him show each step with the blocks, write the step, then show the next step with the blocks.

Eventually, the traditional algorithm is much faster. Any problem that's incorrect had to be shown with the blocks.

 

I really like base 10 blocks for all 4 basic arithmetic operations.

I also like how using the blocks shows what's going on with the traditional algorithms too.

[klmama]

Thanks for sharing this method! I hope you figure out a way to explain it so your dd can understand.

[Snickerdoodle]