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It really depends on how you are calculating the historical exchange rate.
This site discusses a variety of ways to calculate it; depending on what index you use, it can be anywhere between $9.6 trillion and $60 trillion. The numbers are only meaningful if you are considering things correctly; I'd lean towards the relative share of GDP (the $60 trillion figure) because that makes more sense in terms of big government spending than does the CPI (the $11.4 trillion figure above), which compares things like how much a loaf of bread costs at any given time. --
24.147.69.31 (
talk)
00:08, 16 January 2008 (UTC)reply
24 is right in pointing at the fact that there are many ways (or indices) to translate a sum of money from one year to another. 11.49 is the amount (of 2006 dollar trillions) one trillion in 1944 represents in purchase power. In other words, what could an average consumer adquire with such amount, translated to present money?
The $60 trillion figure 24 mentions is built like this: What percentage of America's
GDP in 1944 did a trillion represent? Then, what's the current value of such a fraction of 2006's GDP?
A country's GDP grows partially because its economy is expanding, and not just because of inflation. Suppose inflation did not exist, and the current cost of all products are identical to the cost of the products in 1945. Calculating the cost of World War II in today's dollars, according to the 1945 percentages of their GDPs countries used, would be misleading. It would imply a much higher cost when expressed in today's dollars, even though the cost of the resources used is the same. In other words, the same resources will "cost" more simply because the country's economy is growing. --
Bowlhover (
talk)
08:10, 18 January 2008 (UTC)reply
Parametric equations
I have just been introduced to parametric equations and I'm having a bit of a hard time finding the derivative of one.
Thank you; everything is working out fine now. I wonder though, since I haven't been taught this and I can't find it in my textbook, is there a way of finding a tangent to a parametric curve at a particular point without using the formula you gave me?
172.142.94.249 (
talk)
20:44, 14 January 2008 (UTC)reply
Depends on what you are allowed to use. The tangent is the line which gives a first order approximation to the curve. Suppose you have . Then your first order approximations for the coordinates of the point corresponding to are and , so the point on the tangent corresponding to t satisfies and . If you eliminate t from these equations, you will have the equation of the tangent. --
Meni Rosenfeld (
talk)
20:53, 14 January 2008 (UTC)reply
Welcome to the Wikipedia Mathematics Reference Desk Archives
The page you are currently viewing is an archive page. While you can leave answers for any questions shown below, please ask new questions on one of the
current reference desk pages.
It really depends on how you are calculating the historical exchange rate.
This site discusses a variety of ways to calculate it; depending on what index you use, it can be anywhere between $9.6 trillion and $60 trillion. The numbers are only meaningful if you are considering things correctly; I'd lean towards the relative share of GDP (the $60 trillion figure) because that makes more sense in terms of big government spending than does the CPI (the $11.4 trillion figure above), which compares things like how much a loaf of bread costs at any given time. --
24.147.69.31 (
talk)
00:08, 16 January 2008 (UTC)reply
24 is right in pointing at the fact that there are many ways (or indices) to translate a sum of money from one year to another. 11.49 is the amount (of 2006 dollar trillions) one trillion in 1944 represents in purchase power. In other words, what could an average consumer adquire with such amount, translated to present money?
The $60 trillion figure 24 mentions is built like this: What percentage of America's
GDP in 1944 did a trillion represent? Then, what's the current value of such a fraction of 2006's GDP?
A country's GDP grows partially because its economy is expanding, and not just because of inflation. Suppose inflation did not exist, and the current cost of all products are identical to the cost of the products in 1945. Calculating the cost of World War II in today's dollars, according to the 1945 percentages of their GDPs countries used, would be misleading. It would imply a much higher cost when expressed in today's dollars, even though the cost of the resources used is the same. In other words, the same resources will "cost" more simply because the country's economy is growing. --
Bowlhover (
talk)
08:10, 18 January 2008 (UTC)reply
Parametric equations
I have just been introduced to parametric equations and I'm having a bit of a hard time finding the derivative of one.
Thank you; everything is working out fine now. I wonder though, since I haven't been taught this and I can't find it in my textbook, is there a way of finding a tangent to a parametric curve at a particular point without using the formula you gave me?
172.142.94.249 (
talk)
20:44, 14 January 2008 (UTC)reply
Depends on what you are allowed to use. The tangent is the line which gives a first order approximation to the curve. Suppose you have . Then your first order approximations for the coordinates of the point corresponding to are and , so the point on the tangent corresponding to t satisfies and . If you eliminate t from these equations, you will have the equation of the tangent. --
Meni Rosenfeld (
talk)
20:53, 14 January 2008 (UTC)reply