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0 pointsIncRnd8y ago0 comments

www.wikihow.com/Calculate-Percentage-Increase

The general equation for an increased quantity from A to B is

  increase = B - A

So a percentage increase is

  increase * 100

not

  (increase + A) * 100

0 comments

mraleph8y ago

but I am not talking about the percentage increase I am talking about increase "by a factor of X" that is X = B/A.

See: https://ell.stackexchange.com/a/52747

Maybe my problem is that I am missing "by".

IncRndOP8y ago

You are exactly talking about percentages.

B/A is the percentage of the new value relative to the old.

(B-A)/A is the percentage of the increase of the value.

This is algebra not English.

1) You start out with one rock. 2) You add another rock, getting a pile of two rocks. 3) The rock pile size is now 200% of the original size. But, the increase of the rock pile size is 100%. 4) According to the rules of algebra, 100% = 1. In this case 100% = 1 rock, since the unit under discussion is rocks.

neurotrace8y ago

They absolutely are not talking about percentages. They're talking about factors. A factor is a term in a multiplication. In standard US English, increasing something by a factor means to multiply it by that number. Even the GMAT uses that phrase in that way. You absolutely can split hairs on this and the phrasing can be confusing but it is absolutely understood that "increased by a factor of 4" means to multiply by 4. If one was talking in terms of percentages, they would say something like "increased by 300%".

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IncRndOP8y ago

I forgot the division in that post, and I can't edit it. See the post below. Sorry.

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