(2) The scratch can also occur in the hundreds, thousands, and so on.

## 5 |
||

## + |
## 1 |
## 0 |

## 2 |
## 5 |

## 3 |
## 0 |

## (/3 make 3 a 4) |

## 4 |
## 0 |

The ones column value is equal to 10. To add the ten, you scratch 3 (which is in the tens value place)to obtain

a value of 4 (one more ten then the orginal 3). Then when added the value is 40.