What number is X% greater than Y?

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by Anurag@Gurome » Thu Sep 01, 2011 11:42 pm
siddhans wrote:Please explain how to write these equations in detail?

1)What number is X% greater than Y?
2)X is what percent greater than Y?
3)X is what percent greater than Y percent of Z?
(1) What number is X% greater than Y?
Let the number, N = X% of Y + Y = (XY/100 + Y)

(2) X is what percent greater than Y?
X = N% of Y + Y
X = NY/100 + Y
So, N = {(X - Y) * 100}/Y

(3) X is what percent greater than Y percent of Z?
X = N% of Y% of Z + Y% of Z
X = NYZ/(100 * 100) + YZ/100
10,000X = YZ(N + 100)
N = (10000X/YZ) - 100
Last edited by Anurag@Gurome on Fri Sep 02, 2011 12:34 am, edited 1 time in total.
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by siddhans » Fri Sep 02, 2011 12:06 am
Anurag@Gurome wrote:
siddhans wrote:Please explain how to write these equations in detail?

1)What number is X% greater than Y?
2)X is what percent greater than Y?
3)X is what percent greater than Y percent of Z?
(1) What number is X% greater than Y?
Let the number, N = X% + Y = 0.0X + Y

shouldnt this be N = (X/100) Y + Y ??? Atleast thats what the answer says ...and similarly the other 2 problems hence i asked this question....

(2) X is what percent greater than Y?
X = N% + Y or X = N/100 + Y
So, N = (X - Y) * 100

(3) X is what percent greater than Y percent of Z?
X = N% + Y% of Z
X = N/100 + YZ/100
100X = N + YZ
N = 100X - YZ

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by Anurag@Gurome » Fri Sep 02, 2011 12:35 am
siddhans wrote: shouldnt this be N = (X/100) Y + Y ??? Atleast thats what the answer says ...and similarly the other 2 problems hence i asked this question....
You are right, I have edited the previous reply.
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by siddhans » Fri Sep 02, 2011 12:20 pm
Anurag@Gurome wrote:
siddhans wrote: shouldnt this be N = (X/100) Y + Y ??? Atleast thats what the answer says ...and similarly the other 2 problems hence i asked this question....
You are right, I have edited the previous reply.
How do you know when to do this? the wording is so confusing ? I did what you did first too..