# Heavenly Half-Percentages

## Dividing a number by 2 gives you the number's half. This is also the reason why ½ is the reciprocal of 2. The word *percent* in mathematics means to divide the number by 100; "X% of Y" means "Divide X by 100, then multiply by Y". Half of a percent is what you get when you divide X by 200 (Since 100 × 2 = 200 & 1/100 × ½ = 1/200) then multiply by Y. So, if you check out the function below...

## (X/2)% of X = X^{2}/200

## Here's a T-table of integers from 0 to 25 in which the function above is used(percentage of X included in 3rd column):

X |
Y | % of X |

0 | 0 | 0% |

1 | 0.005 | 0.5% |

2 | 0.02 | 1% |

3 | 0.045 | 1.5% |

4 | 0.08 | 2% |

5 | 0.125 | 2.5% |

6 | 0.18 | 3% |

7 | 0.245 | 3.5% |

8 | 0.32 | 4% |

9 | 0.405 | 4.5% |

10 | 0.5 | 5% |

11 | 0.605 | 5.5% |

12 | 0.72 | 6% |

13 | 0.845 | 6.5% |

14 | 0.98 | 7% |

15 | 1.125 | 7.5% |

16 | 1.28 | 8% |

17 | 1.445 | 8.5% |

18 | 1.62 | 9% |

19 | 1.805 | 9.5% |

20 | 2 | 10% |

21 | 2.205 | 10.5% |

22 | 2.42 | 11% |

23 | 2.645 | 11.5% |

24 | 2.88 | 12% |

25 | 3.125 | 12.5% |

### If you exclude the percent sign(%) in the 3rd column, every number in that column is half of the number in the 1st column! (It's true for each row!) I put the half-integers & other non-integers in the 2nd column in decimal form for quickness & ease. All odd numbers have half-integers as halves; even numbers have whole integers as halves!

## X can be any real number you want in this eXcellent function! Get it? I capitalized the "X" in excellent! The dependent variable Y will never be undefined! Dividing the square of X by 200 will give you the number in the 2nd column for each row!

## Here's an interesting example: If X = the square root of 2, then Y = 0.01 in this function! That non-integer is *rational!* Half of the square root of 2 is also its reciprocal, by the way!

### Note: This function also works with imaginary numbers, but the dependent variable will be negative. With complex numbers, (a *real number* + an *imaginary number*) the dependent variable will be an imaginary number.

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© Derek Cumberbatch