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?