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Post by leonardo on Dec 22, 2004 21:37:50 GMT
Bit a mathematical conundrum of here. Hope someone can help! Here is an example of my problem. 180 minutes (3 hours) 96 minutes (1 hour 36 minutes) 74 minutes (1 hour 14 minutes) When I add these up on the calculator I get 350 minutes, which we know is 5 hours 50 minutes. However, why is it when I divide the 350 by 60 in order to determine how many hours and minute are in 350 minutes, I get 5.83333333333333333333. I can work it out in on some paper but is there anyway around this using a calculator? Thanks in advance
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bod
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UGLE - MM (London), MMM RAM(Middx), OSM (London)
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Post by bod on Dec 22, 2004 22:09:10 GMT
The problems stems from the fact that the calculator is working in decimal - base ten, and time is measured in base 60. For example - 15 minutes on a watch face could be entered on a calculator as .25 as it is a quarter of one hour. So 5 hours 50 minutes = 350 single minutes, but because the calculator works in decimal it presents it as 5.83 recurring, and not 5.50. Or something like that......
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Post by leonardo on Dec 22, 2004 22:22:23 GMT
Thanks Bod,
Is it possible it could also work in fractions. For example; we se that because the 8 is behind the decimal point, this means that it is eight tenths. Because we are dealing with 60 minutes as a whole, on e thenth is equal to 6, therefore, 0.83 multiplied by 6 is equal to 4.98, almost the number 5 we're looking for.
Is it possible?
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bod
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Post by bod on Dec 22, 2004 22:37:35 GMT
Definitely on the right lines, 5 minutes is 1/12 of one hour. If you were to work out what the decimal representation of your initial times were - i.e. 180 minutes would be entered as 3.00, 75 minutes would be 1.25 , 1 hour 30 would be 1.50 5 hours 45 minutes would be 5.75, etc. Does that help - or have I just confused you more?
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Post by leonardo on Dec 22, 2004 23:07:25 GMT
Does that help - or have I just confused you more? Bod...Confused more. Is my response ;D ;D I know what you mean but it just seems a long way to go round. I think I'll have to stick to pen and paper. But thanks for having a stab at it.
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bod
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Posts: 1,296
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Post by bod on Dec 22, 2004 23:50:00 GMT
We have to enter our timesheets in decimal - needless to say I round up to nearest quarter of an hour
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