Trade First Subtraction is the focus algorithm (the algorithm to LEARN until you can do it automatically and easily)!
How to use Trade First Subtraction Algorithm when you have a 4-digit number!
When you use the Trade-First Subtraction algorithm and have to trade from the 100's place into the 10's place into the 1's place because there is a number like 504 on the top!
Here is how to use a writing shortcut when you use the Trade-First Subtraction algorithm.
Before you learn the Trade First Algorithm, you may learn the Expand and Trade Subtraction method. This method is GREAT because you can really see what happens in each place when you subtract!
6 Ballfield Road, Lincoln, MA 01773 781.259.9400 fax: Report Inaccessible Content
Lincoln Public Schools
6 Ballfield Road, Lincoln, MA 01773
Report Inaccessible Content