Converting pesos to dollars and vs versa
DanielLee
Hi,
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.
Any Assistance appreciated.
Adios for now,
Daniel Hallas
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Jim Spriggs
DanielLee wrote:
>
> Hi,
>
> Lets say (for example) that I convert $1,000 dollars to Mexican pesos
> at 11% and end up with $11,000 pesos.
Why 11 _percent_?
>
> 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
Also, why are you writing $blah pesos? Do you mean $blah or blah pesos?
> x .090 which gives me $990 dollars, I am missing $10 dollars.
In "real life" you will loose out. The bureaux de change have to make a
profit somehow.
> 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.
I don't think you do, I think you want to change one at the inverse of
the rate at which you change the other. So if
x dollars = xk pesos
then
y pesos = y/k dollars.
--
I don't know who you are Sir, or where you come from,
but you've done me a power of good.
Darrell
"DanielLee" <dlh...@yahoo.com> wrote in message
news:1122232333.5...@g14g2000cwa.googlegroups.com...
>
> Hi,
>
> Lets say (for example) that I convert $1,000 dollars to Mexican pesos
> at 11% and end up with $11,000 pesos.
First, exchanging $1,000 for 11,000 pesos is not an 11% exchange rate. It's
an 1100% exchange rate. (Review the definition of "percent.")
>
> 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.
In one direction of exchange you have:
(something)*(rate) = (something else)
You want the rate in the *other* direction such that exchanging back will
result in the original money you started with.
Remember, the pesos you now have (the "something else") are equivalent to
something*rate from the above equation. Well, what do you need to multiply
(something)*(rate) by in order to get back the original "something?"
1/rate, right? That lets the r's essentially "cancel."
IOW, the two exchange rates are reciprocals of each other. In your case, an
1100% (or simply "11") exchange rate in one direction means a 1/1100% (or
1/11) rate in the other direction. Since percent means parts of 100, this
results in:
1100% = 1100/100 = 11 ...for $ to pesos
1/1100% = 100/1100 = 1/11 ...for pesos to $
In your example, you exchange $1,000 for 1000*11 = 11,000 pesos, or exchange
11,000 pesos for (11000)/11 = $1,000.
--
Darrell
ticbol
$1,000 dollars to Mexican pesos at 11% is $11,000 pesos?
No.
Maybe you mean at 11pesos to the dollar. Or, $1 = 11pesos.
So the rate of change is $1 = 11pesos.
For you to use that in your conversions from $ to pesos, or from pesos
to $, we transform it into a conversion factor (that is only another
name for "rate", so don't worry):
($1/11pesos) or (11pesos/$1).
Why two conversion factors? Zeez, yeah, they look two, but in reality
they are only one, or they are the same. And there is a reason why they
look two.
The idea is to use a version of the conversion factor such that its
denominator is the same in currency as the one you are trying to
convert.
If you want to convert $ to pesos, you multiply that by (11pesos/$1).
If you want to convert pesos to $, you that by ($1/11pesos).
So, say you want to know much is $1000 in pesos.
Just multiply that by (11pesos/$1).
$1000*(11pesos/$1)
The $ sign cancels out,
= 1000*11pesos
= 11,000 pesos.
How about what is 11,000 pesos in dollars?
Why, just multiply that by ($1/11pesos).
11,000pesos*($1/11pesos)
The "pesos" cancels out,
= 11,000*$1/11
= $1000.
In your example you multiplied the 11,000pesos by 0.090.
Why?
That is not correct, that is why you got $990 only.
---------------
Say you want to convert 330 pesos into $.
330pesos*($1/11pesos)
= 330*$1/11
= $30
545 pesos?
545pesos *($1/11pesos)
= $545/11
= $49.55
etc...
Bob
On Mon, 25 Jul 2005 21:29:23 GMT, "DanielLee" <dlh...@yahoo.com>
wrote:
>
>Hi,
>
>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.
>
Neither step above makes sense.
You seem to be saying that there are 11 pesos per dollar. (That is NOT
11%).
To convert $ to peso, multiply by 11. To convert from pesos to
dollars, divide by 11.
If you took any quantitative science in high school or college, you
should have learned a little tool called dimensional analysis (or
factor label, or such). This is a great place for it.
bob
Kevin Karplus
On 2005-07-25, DanielLee <dlh...@yahoo.com> 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 kar...@soe.ucsc.edu http://www.soe.ucsc.edu/~karplus
Professor of Biomolecular Engineering, University of California, Santa Cruz
Undergraduate and Graduate Director, Bioinformatics
(Senior member, IEEE) (Board of Directors, ISCB)
life member (LAB, Adventure Cycling, American Youth Hostels)
Effective Cycling Instructor #218-ck (lapsed)
Affiliations for identification only.
Jeffrey Turner
DanielLee wrote:
> Hi,
>
> 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.
>
> Any Assistance appreciated.
>
> Adios for now,
>
> Daniel Hallas
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.
--Jeff
--
The shepherd always tries to persuade
the sheep that their interests and
his own are the same. --Stendhal
DanielLee
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 @ 10.683 = $10,682.750 pesos
When I am converting pesos to dollars the exchange rate is shown like
this
$10,682 pesos @ 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 @ 10.000 = $10,000 pesos
$10,000 pesos @ .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 @ 10.5000 = $10,500 pesos
$10,500 pesos @ .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
--
Kevin Karplus
On 2005-07-27, DanielLee <dlh...@yahoo.com> wrote:
> $1,000 usd @ 10.683 = $10,682.750 pesos
>
> When I am converting pesos to dollars the exchange rate is shown like
> this
>
> $10,682 pesos @ 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.
Indeed it does not. 1/10.5 is approximately 0.95238 (more precisely,
it is 0.95238095238095238...).
> What I would like to know now is how do I do the math to get the
> inverse number?
The multiplicative inverse of a number is 1 divided by the number.
(Technically, this statement is a bit backward, as division is defined
as multiplication by the multiplicative inverse, but the basic idea,
that multiplying a number by its multiplicative inverse gives you 1,
is the key point.)
So if you have 10.5 pesos per dollar, you have 1/10.5 dollars per peso.
You really only need one exchange rate (if there is no markup or
commission being computed). You then multiply by the exchange rate to
do the conversion in one direction, and divide by it to do the
conversion in the other direction.
$1000 * 10.5 pesos/dollar = 10,500 pesos
10,500 pesos / 10.5 pesos/dollar = $1000
------------------------------------------------------------
Kevin Karplus kar...@soe.ucsc.edu http://www.soe.ucsc.edu/~karplus
Professor of Biomolecular Engineering, University of California, Santa Cruz
Undergraduate and Graduate Director, Bioinformatics
(Senior member, IEEE) (Board of Directors, ISCB)
life member (LAB, Adventure Cycling, American Youth Hostels)
Effective Cycling Instructor #218-ck (lapsed)
Affiliations for identification only.
Jim Spriggs
DanielLee wrote:
>
> $1,000 usd @ 10.683 = $10,682.750 pesos
>
> $10,682 pesos @ 0.09361 = $999.92980 dollars
>
> $1,000 dollars @ 10.000 = $10,000 pesos
>
> $10,000 pesos @ .10000 = $ 1,000 dollars
>
> $1,000 dollars @ 10.5000 = $10,500 pesos
>
> $10,500 pesos @ .09500 = $997.50 dollars
>
What do you mean by, e.g., $10,682 pesos? Is it $10,682 or 10,682
pesos?
Why do you put dollar signs in front of everything?
--
I don't know who you are Sir, or where you come from,
but you've done me a power of good.
Bob
On Wed, 27 Jul 2005 03:02:15 GMT, "DanielLee" <dlh...@yahoo.com>
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 @ 10.683 = $10,682.750 pesos
>
>When I am converting pesos to dollars the exchange rate is shown like
>this
>
>$10,682 pesos @ 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 @ 10.000 = $10,000 pesos
>
>$10,000 pesos @ .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
Dave Chamberlain
DanielLee <dlh...@yahoo.com> wrote:
: For Example this works
: $1,000 dollars @ 10.000 = $10,000 pesos
: $10,000 pesos @ .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 @ 10.5000 = $10,500 pesos
: $10,500 pesos @ .09500 = $997.50 dollars
: If I understand Kevin correctly I just did not carry it out far enough?
This is a yes AND no answer...
On one side of the coin, it is because it wasn't brought out far enough,
on the other side of the coin, it is because .09500 is not the right number
but is close.
As a basic explanation:
It may be the way you're using the decimal number. A decimal number is a
representation of a fraction. A fraction is a representation of a
ratio. When doing the conversions you're doing, you may find it
easier to think along the lines of a ratio.
10.5 pesos for every 1 dollar
A ratio of 10.5:1
As a fraction that's: 10.5/1 or 10.5
So the conversion is to multiply dollars by the cvonersion ratio of 10.5.
x dollars * 10.5 conversion ratio gives you y pesos
To do the opposite you need to flip things around. You're now saying
that you will receive 1 dollar for every 10.5 pesos. A ratio of 1:10.5
As a fraction that is 1 / 10.5. Which is .095238 (repeated) -- you'll
notice it is close to what you had, but it was arrived at differently
and therefore gave a number closer to the actual number.
10,500 * .095238 will only be 999.999 because yes, it wasn't carried out
far enough. Hence the "yes and no" answer.
-dave
DanielLee
Jim Spriggs wrote:
>
> What do you mean by, e.g., $10,682 pesos? Is it $10,682 or 10,682
> pesos?
>
> Why do you put dollar signs in front of everything?
Hi Jim,
Here is the answer to your question
http://www.alt-usage-english.org/excerpts/fxorigin.html
Jim Spriggs
DanielLee wrote:
>
> Jim Spriggs wrote:
> >
> > What do you mean by, e.g., $10,682 pesos? Is it $10,682 or 10,682
> > pesos?
> >
> > Why do you put dollar signs in front of everything?
>
> Hi Jim,
>
> Here is the answer to your question
>
> http://www.alt-usage-english.org/excerpts/fxorigin.html
Interesting, confusing, deliciously nutty.
--
I don't know who you are Sir, or where you come from,
but you've done me a power of good.
--