From kde-edu Thu Aug 08 11:58:41 2002 From: Uwe Thiem Date: Thu, 08 Aug 2002 11:58:41 +0000 To: kde-edu Subject: Re: [kde-edu]: unified kde-edu style? X-MARC-Message: https://marc.info/?l=kde-edu&m=102880801622318 On Thursday 08 August 2002 12:36, Dominique Devriese wrote: > Sebastian Stein writes: > > > > - the possibility to practic conversions from fractions to decimal numbers > > > and vica versa. 1/8 = 0.125 > > > > Ok. Do you know a good algorithm to convert 0.125 into 1/8? > > err, you interpret it as 125/1000 and then you simplify ? > > there's also an algorithm to convert decimal numbers of infinite > length, but with a repeating part ( which means the decimal > representations of all rational numbers ) into fractions... I think > the idea was to divide the repeating part by a number which you write > down as x 9's where x is the length of the repeating part ( that's the > best i can explain it in english :). E.g. 0,111... would become 1/9 > . 0.1212... would become 12/99 etc. This is the way they explained > it to us in high school, i'm sure there's an easy way to write this > down in code... With a being your periodical decimal number and n being the length of the period, you multiply a by 10^n and then subtract a: a = 0.1111111 10a = 1.1111111 9a = 1 a = 1 / 9 b = 0.213213213213 1000b = 213.213213213213 999b = 213 b = 213 / 999 Uwe -- Nothing is fool-proof given a sufficiently skilled fool. _______________________________________________ kde-edu mailing list kde-edu@mail.kde.org http://mail.kde.org/mailman/listinfo/kde-edu