Percentage

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?

	50% means 50 per 100 (50% of this box is green)

 

25% means 25 per 100 (25% of this box is green)

Examples:

		100% means all. Example: 100% of 80 is 100100 × 80 = 80
		50% means half. Example: 50% of 80 is 50100 × 80 = 40
		5% means 5/100ths. Example:5% of 80 is  5100 × 80 = 4So 75% really means  75100 And 100% is 100100, or exactly 1 (100% of any number is just the number, unchanged) And 200% is 200100, or exactly 2 (200% of any number is twice the number) A Percent can also be expressed as a Decimal or a Fraction   A Half can be written...       As a percentage: 50% As a decimal: 0.5 As a fraction: 1/2 Read more about this at Decimals, Fractions and Percentages. Some Worked Examples Example: Calculate 25% of 80 25% = 25100 And  25100 × 80 = 20 So 25% of 80 is 20 Example: 15% of 200 apples are bad. How many apples are bad? 15% = 15100 And  15100 × 200   =  15 × 200100      =  15 × 2       =  30 apples 30 apples are bad Example: if only 10 of the 200 apples are bad, what percent is that? As a fraction, 10200 = 0.05 As a percentage it is: 10200 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% = 25100 And  25100 × $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.