On Wed, 27 Jul 2005 03:02:15 GMT, "DanielLee" <dlh3648@[EMAIL PROTECTED]
>
wrote:
>
>
>Thank you all for your replies,
>
>I made a mistake of saying 11% in my original post, obviously that was
>not the right way to state the question.
>
>The original question comes from the way they do exchange rates on
>Internet Currency Converters like this one on Yahoo. (You may have to
>splice the link together in your browser to get it to work).
>
>http://finance.yahoo.com/currency/convert?amt=845&from=USD&to=MXN&submit=Convert
>
>When I am converting dollars to pesos the exchange rate is shown like
>this
>
>$1,000 usd @[EMAIL PROTECTED]
10.683 = $10,682.750 pesos
>
>When I am converting pesos to dollars the exchange rate is shown like
>this
>
>$10,682 pesos @[EMAIL PROTECTED]
0.09361 = $999.92980 dollars
>
>I know that the exchange rate may be different for each conversion
>depending on currency values or what ever. I was figuring that the
>dollar to peso number of 10.683 could lead me to the number I needed if
>I wanted to convert pesos to dollars at the same rate.
>
>It seems that since a dollar to peso rate of 10.000 is equal to a pesos
>to dollar rate of 0.10000. Or stated another way (10 before the decimal
>point was equal to 10 after the decimal point) then a 10.5000 number
>before the decimal point would equal a .09500 (or some such number)
>after the decimal point. That the addition to one would equal the
>subtraction from the other. But when I do it that way it does not work.
>
Addition and subtraction are not relevant. It is multiplication and
division. In one case you multiply by 10, in the other you divide by
10. If you want something to multiply by for the second case, it is 1
over the original 10. Or in your example above, it is 1 over 10.5000,
which is 0.0952381. (This is the inverse, which you discuss below.)
>For Example this works
>
>$1,000 dollars @[EMAIL PROTECTED]
10.000 = $10,000 pesos
>
>$10,000 pesos @[EMAIL PROTECTED]
.10000 = $ 1,000 dollars
That is because 1/10.000 is 0.10000
>
>Adding .5 to the dollar to peso and subtracting .5 from the pesos to
>dollar does not work
correct; need to do mult and divide; see above.
>
>The inverse of 11 is 0.0909090909... which will give you the
>full $1000 back. You just lost a bit of precision in using 0.090.
>
>What I would like to know now is how do I do the math to get the
>inverse number?
Divide 1 by the number. Some calculators have a key to do it directly;
maybe labeled 1/x. Try it. The inverse of 3 should give you 0.33333...
bob
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