Re: Stephen's List
enile, on host 195.54.240.4
Wednesday, June 9, 1999, at 07:14:31
Re: Stephen's List posted by Else on Wednesday, June 9, 1999, at 05:35:16:
> > Also (to the nearest second): > > 1: 4.05.27 > > 2: 4.21.49 > > 3: 4.38.11 > > 4: 4.54.33 > > > > enile ;) > > G*D but you're GUD! How do you do it? I suppose you had use of a PC and a math program. But if you remember I only had use of 'improper fractions' back in 1955 in year 5 of high school (don't ask how old I am), I'd appreciate a few notes on how you approach the problem? > > Thanks for your time enile ;) you're real sweet!
No PC, no sleight of hand - just good old algebra:
Suppose the time is 4 hours and t minutes Each 'hour' on the clock face is 30deg Position of hour hand is: (4 x 30deg) + (t/60 x 30deg) = (120 + t/2)deg Position of minute hand is: t x 360/60deg = 6t
So, if we want the angle between the hands to be y degrees (where y = -90, 0, 90, 180) we solve the equation: 6t - (120 + t/2) = y rewritten as t = (120+y)/5.5 remembering that t returned is in decimal minutes, so to convert to minutes and seconds take the bit after the decimal point (the seconds component) and multiply by 60 (eg 1.5 minutes = 1min + 60x0.5sec).
Always glad to help someone with their homework (can't work out how old you are though;)
en'once was a mathematician'ile
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