Lyon and Tiger were on a roll this morning. This was their effort and they wanted a record kept on our blog. The research was theirs; I only helped with the edits. If anyone out there finds the contents of the table useful, brilliant.

DIVISIBLE BY: | TEST | EXAMPLE |

2 | If the last digit is an even number | 1002 or 19904 or 345402 |

3 | If the sum of the digits is divisible by 3 | 540 or 207 |

4 | If the last two digits are divisible by 4 | 1040 or 99948 |

5 | If the last digit is 0 or 5 | 1000 or 99905 |

6 | If the number is divisible by both 2 AND 3 | 1002 or 2136 |

7 | If 7 is a factor of the number | 7 or 42 or 63 |

8 | If the last 3 numbers are divisible by 8 | 10106 or 99839080 |

9 | If the sum of the digits is divisible by 9 | 1008 or 9000 |

10 | If the last digit is 0 | 1730 or 3330 |

11 | If the difference between the sum of all alternate digits is zero or 11 for example, the number 1320, 1 + 2 = 3; 3 + 0 = 3. The difference between the two sums is zero so the number is divisible by 11. Another way of doing this is placing + and – before alternate digits to check if the result is zero or 11 so using 1320 again, +1-3+2-0 = 0 so 1320 is divisible by 11. | 1320 or 1419 |

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