How do you find the percentage change?

Question

I have a problem here...how do you find the percentage change from somthing that use to cost 4 dollars but now costs 6? I need to know how to do percentage changes, would someone explain it to me clearly?

Um...thats wrong...my book says something else...

Answer 1

Percentage Change = (P1)/(P0)-1

Where P1 = Price now (6)
and P0 = Price before (4)

(6/4)-1 = 1.50 = 0.50 = 50%

Addendum: No wonder you can't figure out the problem. Your book is wrong. Trust me... it's 50%. Click on one of the following links and they will back me up...

http://www.csgnetwork.com/percentchangecalc.html
http://www.notrain-nogain.org/Train/Res/Num/numbers.asp
www.newsengin.com/neFreeTools.nsf/PercentChange/formPercentChange
http://en.wikipedia.org/wiki/Percentage

Answer 2

percentage change is generally computed as :
new price less old price/ old price
which is also the same as the person above's solution....

dont know how your book explains it, but the increase of $2 dollars is really 50% of the original price of $4. so when asked, how much is the percentage increase you say 50% which can be doubled checked when you multiply the percentage increase by the original price + the original price or for simpler formula: original price*(1+%change)


p.s. dont always believe your books... :)