Percent:

In math, a percentage is a way of showing a number as a fraction out of 100 (per cent meaning "per hundred").

This is the percent sign = %. For an example 67% is equal to 67/100 or .67.

Percentages are used to show how large one thing is to another.

  Percentages can be converted into a ratio:

To convert a percent to a ratio, you have to convert the percent to a fraction by putting the percent over 100.Then you put the numerator as the 1st part and the 2nd part will be the answer of the denominator-the numerator.

  Percentages can be converted in a fraction:

To convert a percent to a fraction, you have to just have to put the percent over 100 to get the fraction.

 Percentages can also be converted into a decimal:

To convert a percent to a decimal, you have to divide the percent by 100.

Proportions:

Percentages are correctly used to express fractions of the total. For example, 50% means 50/100 or "one half".

Calculations:

To find the percentage of a single unit in the whole, divide 100 by the whole. For an example, if you have 200 pennies, and you want to find out what percentage of the 200 pennies a single penny represents, 100/200 would provide the answer of 0.5.

To calculate a percentage of a percentage, convert both percentages to fractions of 100, or to decimals, and multiply them. For example, 50% of 20% is:

(50/100)(20/100)=(0.5)(0.2)=0.1

Here are some examples:

1. What is 200% of 30?   30/100=0.3x200=60

2. What is 13% of 98?     98/100=0.98x13=12.74

Problem:

Suppose a certain item used to sell for fifty cents a pound, you see that it's been marked up to seventy-one cents a pound. What is the percent increase?

Percent Test