Percentages (%)

When we say "Percent" we are really saying "per 100"
One percent (1%) means 1 per 100.

1% of this line is shaded green: it is very small isn't it?

Using Percent
When 100% =

then:

75% = 60

Use the slider and try some different numbers (What is 40% of 80? What is 10% of 200? What is 90% of 10?)

Because "Percent" means "per 100" think:
"this should be divided by 100"

So 75% really means  75 100

And 100% is  100 100, or exactly 1 (100% of any number is just the number, unchanged)

And 200% is  200 100, or exactly 2 (200% of any number is twice the number)

A Percent can also be expressed as a Decimal or a Fraction
Read more about this at Decimals, Fractions and Percentages.

Example: Calculate 25% of 80
25% =  25 100

And   25 100  × 80 = 20

So 25% of 80 is 20

Example: 15% of 200 apples are bad. How many apples are bad?
15% =  15 100 30 apples are bad

Example: if only 10 of the 200 apples are bad, what percent is that?
As a fraction,  10 200  = 0,05

As a percentage it is:  10 200  x 100 = 5%

5% of those apples are bad

=== Example: A Skateboard is reduced 25% in price in a sale. The old price was $120. Find the new price. === First, find 25% of $120:

25% =  25 100

And   25 100  × $120 = $30

25% of $120 is $30

So the reduction is $30

Take the reduction from the original price

$120 − $30 = $90

The Price of the Skateboard in the sale is $90

Calculation Trick
This little rule can make some calculations easier:

x% of y = y% of x

Example: 8% of 50
8% of 50 is the same as 50% of 8

And 50% of 8 is 4

So 8% of 50 is also 4

The Word
"Percent" comes from the latin Per Centum. The latin word Centum means 100, for example a Century is 100 years.

Percent vs Percentage
My Dictionary says "Percentage" is the "result obtained by multiplying a quantity by a percent". So 10 percent of 50 apples is 5 apples: the 5 apples is the percentage.

But in practice people use both words the same way.