CH 5 percentages Flashcards
1
Q
What is the automatic way of expressing: “What % of 50 is 30”
A
Keyword: OUT OF. 30 out of 50.
30/50 * 100 = x%
2
Q
% change: “the price increased from 80 to 84. By what % did price change?”
A
% change = (change / original). 4/80 = x/100. So 1/20 = x100; so x=5
3
Q
New %. “The price of $30 decreased by 20%, what is final price?”
A
new % = new value / original value.
80% = x/30, or 80/100 = x/30; x =24
4
Q
The original number - what does this mean?
solve: 10% increase is x % of original?
solve: 45% decrease is y % of original?
A
The original number will always be 100%
x = 110% of original
y = 55% of original
