There are two
main types of problems dealing with percents:
|
1.
|
The
first type of problem is when the percent
is given.
In these problems, you must change the percent to a
decimal.
|
|
To
change a percent to a decimal, divide the number by 100.
This will move the decimal point two places to the left.
| Example: |
Find
7% of 250.
(Remember
7%=0.07)
Let x = the
answer
0.07 (250) = x
17.5 = x
|
|
Remember that
the word "of" means
to multiply! |
|
| Example: |
30 is
15% of what number?
(Remember
15%=0.15)
Let n = the
answer
30 = 0.15 n
n = 200 |
|
2.
|
The
second type of problem is when you are looking
for the percent.
In these problems, you should put a variable over a 100.
|
|
| Example: |
4
is what percent of 12?
Let x =
the
percent.
Writing
this problem literally we would get:
4 = x% of 12.
12x = 400
x =
 %
|
|
To
change a percent to a decimal, divide the number by 100. |
|
|
