Lets use 1 to solve this problem because it is easiest to show.
Multiply 1 by 1.3 for a 30% increase (1*1.3=1.3).
Then multiply 1.3 by .7 for a 30% decrease. (1.3*.7=.91)
Therefore the page had a 9% reduction from its original size or is 91% of its original size.
80/100 x 30 = 24 because you just multiply percents
I'm not sure what side is missing but you could use the proportions
A/B=X/Y or B/C=Y/Z or CA/=ZX. it also works if you reverse this for example B/A=Y/X
The price of an item has dropped to $84 today. yesterday it was $120 . find the percentage decrease.
