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Topic: Converting pesos to dollars and vs versa
Replies: 6   Last Post: Jul 26, 2005 11:02 PM

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Kevin Karplus

Posts: 190
Registered: 12/6/04
Re: Converting pesos to dollars and vs versa
Posted: Jul 26, 2005 1:03 PM
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On 2005-07-25, DanielLee <> wrote:
> Lets say (for example) that I convert $1,000 dollars to Mexican pesos
> at 11% and end up with $11,000 pesos.
> Now lets say I want to convert $11,000 pesos to dollars at the same
> rate. The way I am doing it now would be to multiply the $11,000 pesos
> x .090 which gives me $990 dollars, I am missing $10 dollars.
> How do I figure out what the peso to dollar exchange rate is using the
> known dollar to peso exchange rate? I want to change pesos to dollars
> at the same rate I changed dollars to pesos.

Using % is a poor way to think of conversions.
These are simple ratios:
pesos/dollars = 11
so dollars/pesos = 1/11 =approx 0.090909

$1,000 dollars * 11 pesos/dollars = $11,000 pesos
$11,000 pesos / (11 pesos/dollars) = $1,000 dollars

$11,000 pesos * (0.090909 dollars/pesos) = $999.999 =approx $1000

Kevin Karplus
Professor of Biomolecular Engineering, University of California, Santa Cruz
Undergraduate and Graduate Director, Bioinformatics
(Senior member, IEEE) (Board of Directors, ISCB)
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