An alternative subtraction algorithm
Download
1 / 5

- PowerPoint PPT Presentation


  • 224 Views
  • Updated On :

Trade-First Subtraction. An alternative subtraction algorithm . 12. When subtracting using this algorithm, start by going from left to right. 8. 12. 13. 9 3 2 - 3 5 6.

loader
I am the owner, or an agent authorized to act on behalf of the owner, of the copyrighted work described.
capcha
Download Presentation

PowerPoint Slideshow about '' - bliss


An Image/Link below is provided (as is) to download presentation

Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author.While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server.


- - - - - - - - - - - - - - - - - - - - - - - - - - E N D - - - - - - - - - - - - - - - - - - - - - - - - - -
Presentation Transcript
An alternative subtraction algorithm l.jpg

Trade-First Subtraction

An alternative subtraction algorithm

Created by Rina Iati, South Western School District, Hanover, PA


Slide2 l.jpg

12

When subtracting using this algorithm, start by going from left to right.

8

12

13

9 3 2

- 3 5 6

Ask yourself, “Do I have enough to subtract the bottom number from the top in the hundreds column?” In this problem, 9 - 3 does not require regrouping.

5

7

6

Move to the tens column. I cannot subtract 5 from 3, so I need to regroup.

Move to the ones column. I cannot subtract 6 from 2, so I need to regroup.

Now subtract column by column in any order

Created by Rina Iati, South Western School District, Hanover, PA


Slide3 l.jpg

11

Let’s try another one together

6

15

12

7 2 5

- 4 9 8

Start by going left to right. Ask yourself, “Do I have enough to take away the bottom number?” In the hundreds column, 7- 4 does not need regrouping.

2

2

7

Move to the tens column. I cannot subtract 9 from 2, so I need to regroup.

Move to the ones column. I cannot subtract 8 from 5, so I need to trade.

Now subtract column by column in any order

Created by Rina Iati, South Western School District, Hanover, PA


Slide4 l.jpg

13

8

12

14

9 4 2

- 2 8 7

Now, do this one on your own.

6

5

5

Let's see if you're right.

Congratulations!

Created by Rina Iati, South Western School District, Hanover, PA


Slide5 l.jpg

9

Last one! This one is tricky!

6

13

10

7 0 3

- 4 6 9

2

3

4

Let's see if you're right.

Congratulations!

Created by Rina Iati, South Western School District, Hanover, PA


ad