Multiplies two 32-bit values and then divides the 64-bit result by a third 32-bit value

#include <WinAPIMisc.au3>

_WinAPI_MulDiv ( $iNumber, $iNumerator, $iDenominator )

$iNumber | Specifies the multiplicand |

$iNumerator | Specifies the multiplier |

$iDenominator | Specifies the number by which the result of the multiplication is to be divided |

Success: | The result of the multiplication and division |

Failure: | (-1), if either an overflow occurred or $iDenominator was 0 |

If the result is a positive half integer (ends in .5), it is rounded up.

If the result is a negative half integer, it is rounded down.

Search MulDiv in MSDN Library.