percentages: Flashcards
one amount as a % of the other amount (wants answer as a %):
a as a percentage of b
a/b x 100
-look for the words as a percent of
percentage gain/loss (wantes answer as a %):
difference/original x 100
-looks for the words percentage gain/loss/increase/decrease
find percentage of an amount:
%/100 x amount
given % of an amount, find the full amount:
given amount/%/100
increasing/decreasing by a %:
amount (1+- %/100)
+ if increase
-if decrease
given % of an amounr after amount has been added or subtracted, find the full amount:
amount/1+-%/100
+ if increase
- if decrease
-look for the words originally, at the beginning, before…
simple interest (interest on initial amount):
amount + (amount x %/100 x time)
interest = amount x %/100 x time
-note: make sure t and % are the same unit of time
compound interest (interest added also earns interest):
FV = PV (1 + r/100)ᵗ
FV = future value, PV = present value
t = time, r = interest rate