# Addition

Look at the examples below before you attempt any of the exercises. It is important to understand how numbers are placed into units, tens, hundreds and thousands.

When you have done the exercises then check your answers.

## Example 1

5 + 5 =?

5 + 5 = 10 enter 0 in the units column and carry 1 to the tens column.

You could even use your fingers to add up two numbers.

Th | H | T | U |
---|---|---|---|

5 | |||

5 | |||

1 | 0 | ||

1 |

+

## Example 2

82 + 37 =?

- 2 + 7 = 9 enter 9 in the units column.
- 8 + 3 = 11 enter 1 in the tens column and carry 1 over to the hundreds column.

Th | H | T | U |
---|---|---|---|

8 | 2 | ||

3 | 7 | ||

1 | 1 | 9 | |

+

## Example 3

145 + 935 =?

- 5 + 5 = 10 enter 0 in the units column

and carry 1 over to the tens column. - 4 + 3 = 7 plus the 1 carried over = 8

enter 8 in the tens column. - 9 + 1 = 10 enter 0 in the hundreds

column and carry 1 over to the thousands

column.

Th | H | T | U |
---|---|---|---|

1 | 4 | 5 | |

9 | 3 | 5 | |

1 | 0 | 8 | 0 |

1 |

+

# VIDEO

Have a look at the demonstration on the video to enhance your learning.

# Adding numbers up in your head

It is more fun adding numbers up in your head!

## Example 1

Add 23 + 55

- Add the tens 20 + 50 = 70
- Add the units 3 + 5 = 8
- Then add up the results 70 + 8

Total= 78

## Example 2

Add 126 + 139

- Add the hundreds 100 + 100 = 200
- Add the tens 20 + 30 = 50
- Add the units 6 + 9 = 15
- Then add up the results 200 + 50 + 15

Total = 265