How to Figure Percentages

One of the most used applied mathematics concepts in many different fields is 'Percentage'. Wherever you deal with numerical data, you need to deal with the concept of percentages. So even if you don't go into the very depths of pure mathematics, you need to understand certain math terms and concepts which find application in day-to-day calculations. You must know the calculation of percentages between two numbers.

Definition
I assume that you already know what are ratios. A percentage or percent is a special kind of a ratio. A percentage is a special kind of proportion of a part, with respect to a whole, which is divided into hundred parts. A percentage of a specific quantity is the specification of the number of parts per hundred total parts, which the whole has been divided in. An example will serve to simplify what I am trying to explain here. Suppose that you take a piece of square land and divide it into hundred sectors. Suppose 5 out of the 100 sectors are bought by some people. Then one could say that 5 percent of the land is sold. A per cent, literally means 'per hundred parts'. It is denoted by a special sign which is exclusively used to denote percentages, which is the '%' sign. Here is the formula.

Percentage = (Part / Whole) x 100

This is the standard formula which you must explain if the multiplication by hundred that you see in the above formula converts any fraction into a percentage. That's the key thing to understand to know how to figure out the percentages between two numbers. Let us now see how to find percentage, in the following lines.

How to Figure Percentages Between Two Numbers
Using the above formula, one can easily figure out calculation of percentages. To be able to compute percentage, you need two numbers among which one will be the 'part' and the other will be the 'whole'. Suppose a student scores a total of 150 marks out of 200. Here the 'part' is 150 and the 'whole' is 200. So using the above formula the percentage of marks scored by the student will be:

(150/200) x 100 = 75%

How to Figure Out Percentage Increase
One of the confusing percentage calculations is that of small incremental changes. Let us see how to calculate percentage increase. Here is a formula to calculate percentage increase.

Incremental Percentage Change = [(Increased Quantity - Original Quantity) / Original Quantity] x 100

Suppose you already had $10,000 stored in your savings and after two more months of fresh influxes, your savings have now increased to $12,000. What is the percentage increase in savings? Using the above formula, the percentage increase in value will be:

Percentage increase in savings = [($12,000 - $10,000) / $10,000] x 100 = 20%

How to Figure Out Actual Values From Percentages
You may wonder about how to get back actual ratios or values from percentages? That is, if you are asked, how much is 8% of $5000, you will have to do the reverse calculation. Here is the formula you may use to convert percentages back to actual numbers.

Part = (Percentage x Whole)

Here the part is the actual share denoted by the percentage and whole is the total value. So to calculate 8% of $5000, you can use the above formula in the following way:

(8/100 x $5,000) = $400

So now you not only know how to figure out the percentages, but also know how to calculate actual ratios from those percentages.

To master the technique of calculating percentages, there is no better way than solving as many examples as possible. As you must have already figured out, you don't need to be an Einstein to understand how to do percentages. It is just a matter of executing one division and one multiplication! With a calculator at hand you can calculate percentage between any two numbers, quite easily.