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Wed 15 Jun, 2005 02:29 pm
If the difference between 12 and 9 is three, and the difference between 9 and 12 is also three...
Then what is the difference between 100% and 150%?
Am I correct that the question cannot be answered as given?
The answer can be give as a percentage - 50%.
What can't be determined is the whole number value of that percentage.
But isn't it only 50% from one perspective? Once you reverse the problem the difference becomes 33%.
I'm trying to establish a difference without respect to order.
I suppose a better way of wording it, is that even subtraction can be commutative, if you're looking for absolute value, but percentages cannot be.
Is that assumption correct?
SCoates wrote:But isn't it only 50% from one perspective? Once you reverse the problem the difference becomes 33%.
How does it only become 33%???? You lost me there.
The difference between 100% and 150% is 50%
The difference between 150% and 100% is 50%
Because 50 is 33% of 150.
SCoates wrote:I suppose a better way of wording it, is that even subtraction can be commutative, if you're looking for absolute value, but percentages cannot be.
Is that assumption correct?
I believe "commutive" only applies to real numbers as a mathmatical principle. (I may be mistaken in this, it's been a long while...)
I certainly don't know myself. I had to look up the property names to find the one I wanted.
Percentage is ((y-x)/x) multiplied by 100, and the difference of percentage numbers is
(z-x)/x - (y-x)/x = (z-y)/x
with both sides multiplied by 100, where x is the base value, z and y are current values.
difference implies addition or its inverse, subtraction. That's a much better answer than what I had typed.
The answer is 50%.
coz if u say 150% and 100%, u first need to define the value at which u are applying these percentages.
150% and 100% actually mean that u are taking one and a half times of one no. and one times of the same no.
so the difference obviously is half of that no. which is 50% from both sides.
You can refer to a percentage increase from a smaller to a larger or percentagr decrease from a larger to a smaller, but you can not refer to a percentage difference between two numbers, because as you state, you get two differnt numbers depending upon which direction you go. Going from 2 to 4 is a 100% increase. Going from 4 to 2 is a 50% decrease.
Well, thanks for everyone's opinions.
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