To solve proportions, follow these simple steps:

__1. Cross Multiply:__

Multiply the denominator of the second
fraction by the numerator of the first.

Multiply the denominator of the first
fraction by the numerator of the second.

EXAMPLE

__2__ = __x__

3 4

8 = 3x

__2. Divide BOTH
sides by the COEFFICIENT of the VARIABLE__

(The variable is the unknown amount, usually
represented by a letter or other symbol. The coefficient
is the number that the variable is multiplied
by. In this case, the variable is x
and its coefficient is 3)

__8__ = __3x__

3 3

2.666... = x

**A percent is a ratio of a number to 100 [Per
= For Each....Cent
= 100]**

**Therefore another way to think about a percent, say 30%, is
30/100.**

**In general,**

**P% = P /100**

You can also write a percent as a decimal.

Remember that when you divide a decimal by 100,

the decimal point moves two places to the left.

So, for example:

**45% = 45/100 = 0.45**

ranging from tax and commission to percent change, discount, interest, and more.

In general, all of these problems follow a basic format:

P = Percent

N = Number

R = Result

of = multiply

Percent of a Number gives a Result

__ P __ x N
= R

100

Which is equivalent to:

__ P __ = __R__

100 N

The important thing to remember is that your percent is always of a
base

(Hence Percent of a number)

this base, when you are given a choice is always the ORIGINAL amount.

Example: What is 15% of 40?

What is your percent? 15

What is your base? 40

What is your result? unknown at this point...use
R

Go to your equation:

__ P __ x N
= R Substitute
all values that you know at this point.

100

__ 15 __ x 40
= R

100

Solve (any way you wish...use as a fractions, reduce, then use as fractions,
or use decimals)

Any way you do this, you should get R = 6.

15% of 40 is 6.