Or if you want to preserve your rounding until the last point in your calculations: | Test 1 | | | 1:15 | 62.50 | 76 | | Test 2 | | | 2:48 | 140.00 | 169 | #+TBLFM: $5=$4*(50/60.0);Df2::$6=$4+1 Since 50/60 is 0.8333... by rounding it prematurely you lose some of the precision in your billing. Column 6 is just there to confirm for me what org does when you add or multiply times. It counts the minutes as units and properly adjusts the hours to be 60*# of hours. So you just have to account for that when billing On Thu, Jul 21, 2011 at 09:37, Giovanni Ridolfi wrote: > Daniel E. Doherty writes: > > > That's certainly thinking outside the box, but I don't think it > > works. > > Actually, Daniel you don't have to *think*, you've to demonstrate > that it works or that it doesn't /tertium non datur/. > > > In your example, 1:09 represents 1/9th in calc's fraction mode, > > not 1+9/60 which it would have to in order to compute with it. > Not with GNU/Emacs 23.3 calc. > > If you bill 50 per 1 hour, you bill > > (/ 50 60.0 ) is 0.83 per minute. > > If you bill 1 hour + 9 minutes it is 69 minutes > > (* 0.83 69) 57.269999999999996 = 57.27 > > isn't it ? > > And the fifth column in my table (see below) does compute 57.27 or not? > > You may say: "Ah but this is only one example, you've been lucky!" > > I reply, what about the second line? > > (* (+ 120 48) 0.83) = 139.44 > > Calc is *really* smart, isn't it? > > cheers, > Giovanni > > > > > Regards, > > > > At Thu, 21 Jul 2011 13:07:28 +0200, > > Giovanni Ridolfi wrote: > >> > >> Daniel E. Doherty writes: > >> > >> > Hi all, > >> > > >> > I am trying to use orgmode to bill for time. My idea is to add a > column > >> > that multiplies the elapsed time column by an hourly rate. > >> > >> what about using a minute rate? > >> > >> (/ 50 60.0) 0.83 so: > >> > >> | Argo Status Hearing <2011-06-28 Tue 09:00> | | | 1:09 | 57.27 | > >> | Letter of Discovery Deficiencies | | | 2:48 | 139.44 | > >> #+TBLFM: $5=$4*0.83;Df2 > >> > >> > >