## Supporting Lessons

## Adding and Subtracting Multiples of 10: Worksheets and Answers

## How to Add or Subtract Multiples of 10

**add 10**to a number using the number grid, we move

**one place down**and when we

**subtract 10**from a number, we move

**one place up**.

In this lesson, we will look at adding and subtracting **multiples of 10** using the number grid.

Above are the first nine multiples of 10.

We can see that:
**10** is **1** lot of 10

**20** is **2** lots of 10

**30** is **3** lots of 10

**40** is **4** lots of 10

**50** is **5** lots of 10

**60** is **6** lots of 10

**70** is **7** lots of 10

**80** is **8** lots of 10

**90** is **9** lots of 10

This tells us how many places we move up or down the number grid.

For example, if we are **adding 40**, we move **4 places down** the number grid, or if we are **subtracting 50**, we move **5 places up** the number grid.

Here is an example of addition using the number grid:

We are asked: what is 24 + 30?

When we add 10, we move 1 place down the number grid.

30 is **3 lots of 10**, so we move **3 places down** the number grid.

We **start at 24** and we move **3 places down** the number grid.

We stop at 54. Therefore,

**24 + 30 = 54**.

Here is an example of subtraction using the number grid:

We are asked: what is 82 – 60?

When we subtract 10, we move **1 place up** the number grid.

60 is **6 lots** of 10, so we move **6 places up** the number grid.

We **start at 82** and we move **6 places up** the number grid.

We stop at 22. Therefore,

**82 – 60 = 22**.