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.
For Example this works
$1,000 dollars @[EMAIL PROTECTED]
10.000 = $10,000 pesos
$10,000 pesos @[EMAIL PROTECTED]
.10000 = $ 1,000 dollars
Adding .5 to the dollar to peso and subtracting .5 from the pesos to
dollar does not work
$1,000 dollars @[EMAIL PROTECTED]
10.5000 = $10,500 pesos
$10,500 pesos @[EMAIL PROTECTED]
.09500 = $997.50 dollars
If I understand Kevin correctly I just did not carry it out far enough?
I don't mean to degrade anyone's method of calculation or explanation
but the ones I felt most helpful were Kevin Karpulus whose answer was
$11,000 pesos * (0.090909 dollars/pesos) = $999.999 =approx $1000
And Jeffery Turner whos answer was
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?
If I may I would like to say a little something, my personal opinion or
observation. I find it interesting the different ways that the problem
was approached, calculated and explained. I am definitely not the
sharpest knife in the drawer especially when it comes to math. Most
explain or process the problem I presented by immediately changing the
dollars and pesos into a symbol or another word. I am sure that there
are reasons for that, like being able to apply the solution to many
situations not just dollars to pesos, but it looses me right off the
bat. Some seem to enjoy kind of shouting at me for not stating the
problem correctly (the percent). I had one hell of a lot of problems in
school when I was young, now that I am older I realize the very special
attributes that a person has to have to be a good teacher. Good
teachers should be sought out and paid huge sums of money; they are
rare people indeed.
I truly appreciate all that took their time to respond to my post in an
attempt to assist me, it is a very generous thing to do. Thank you.
Now if I can learn how to calculate the inverse number (it is probably
in one of the post above) I would appreciate it.
Adios for now,
Daniel Hallas
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