2. Addition and subtraction

Lesson

Before you practice the work from this chapter, take some time to go over how we were able to use place value columns to set up a vertical algorithm. This is useful to solve addition and subtraction problems, instead of using:

- place value models
- number lines
- partitioning to break our numbers up

We also looked at how to use a vertical algorithm to solve addition or subtraction where we needed to regroup our numbers.

We also saw a mix of addition and subtraction problems of different lengths, where we may, or may not, need to do some regrouping.

Find the value of $150+250$150+250.

Find the value of $6754-939$6754−939.

Find the value of $7215+7039$7215+7039.

Remember!

When we use a vertical algorithm, we need to make sure our digits are lined up so they are in the correct place. If we need to regroup, we regroup to the left for addition, and to the right for subtraction.

Apply place value to partition, rearrange and regroup numbers to at least tens of thousands to assist calculations and solve problems