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I have the following equation:

$\frac{n\times2.2046}2\times0.0284130625$

to: convert kg to lbs, divide by $2$, then convert the result from oz to L

is there a shortcut to do this without the conversion to imperial?

yeah, I know this is probably a very elementary question, math has never been my strong suit.

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    The kilogram is a unit of *mass*, while the liter is a unit of *volume*...2012-08-09
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    What are you *actually* trying to calculate?2012-08-09
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    this is a nutrition thing: basic amount of water before factoring in environment, etc = half of body weight (in pounds) in oz of water per day, hence the mass to volume conversion.2012-08-09
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    "this is a nutrition thing: basic amount of water before factoring in environment" - should've mentioned that to begin with. Where did you obtain this formula?2012-08-09
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    sorry, J.M., I should have explained that better. If you mean the equation for lbs:oz, I have found it in various places, couldn't give you an exact reference without searching it out again, it gives a similar result to 1L:1000cal. As for the equation above, it was what I was able to come up with myself to take a stored metric value, perform the imperial equation, and return a metric result.2012-08-09

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$1$ pound is $16$ ounces, and $1$ litre of water has mass very, very close to a kilogram (apparently only about 0.999975 kg). So you should be able to multiply the mass in kg by $\frac{1}{32} = \frac{1}{2} * \frac{1}{16}$ to get effectively the same result.

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    Thank you very much, this seems to give a satisfactory result. In my case, I expressed it as kg*0.03125, is this correct?2012-08-09
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    @bee.catt It's the same2012-08-09
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    That is, half an ounce per pound. But OP's formula (and yours as well) do not account for the mass of a liter (which has nothing to do with the problem); they both also ignore the difference between a pound of water (weight) and 16 fluid ounces of water (a US fluid pint, by volume, which weighs 1.04375 pounds, despite the American saying "A pint's a pound".) However, if it clear that the _assumption_is that the body weight is in _pounds avoirdupois_, but the water is measured in _US fluid ounces_, the difference between a pint and a pound doesn't matter.2015-07-29
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    But keep in mind, if you are in a Commonwealth country that uses Imperial fluid ounces, you don't need quite as many as you would of US fluid ounces, because an Imperial fluid ounce is about 4% bigger than a US fluid ounce.2015-07-29