Important Formula: Percentages | IBPS Clerk Prelims 2024 Preparation - Bank Exams PDF Download

It is represented by % symbol. In all the fractions where the denominator is 100 we remove the denominator and put the % sign.

Calculating the Percentage of a Number

To calculate the percentage of a number, we need to use a different formula such as:

P% of Number = X

where X is the required percentage.

If we remove the % sign, then we need to express the above formulas as;

P/100 * Number = X

Let us understand with help of some examples.

Example: Calculate 10% of 80.
Solution:Let 10% of 80 = X

10/100 * 80 = X

X = 8

Example:The number 450 is what percentage of 1200?
Solution: = (450/1200) × 100

By simplifying the fraction, we get

= (3/8) × 100 

= 0.375 × 100

= 37.5%

So, the number 450 is 37.5% of 1200.

Example: Convert 0.32 to percentage.
Solution:Multiplying 0.32 by 100, we get 0.32 × 100 = 32% as the answer.

Example: Convert the fraction 23/25 to percentage.
Solution: Converting 23/25 to a decimal value, we get 0.92. 

So, 0.92 × 100 = 92% is the answer.

Percentage Increase and Decrease

(i) Percentage Increase

The percentage increase is equal to the subtraction of the original number from a new number, divided by the original number and multiplied by 100.

% increase = [(New number – Original number)/Original number] x 100

where, increase in number = New number – original number

(ii) Percentage Decrease

Similarly, a percentage decrease is equal to the subtraction of a new number from the original number, divided by the original number and multiplied by 100. 

% decrease = [(Original number – New number)/Original number] x 100

Where decrease in number = Original number – New number

(iii)Percentage Formula in terms of a Fraction

To transform a fraction into a percentage divide the top/numerator number by the bottom/denominator number and lastly multiply the result by 100%.

(iv)Percentage Change Formula

Sometimes when it is required to get the increase or decrease in any quantity as percentages, which is also directed to as percentage change is given by the formula:

How to Find Percentage?

To estimate the percentage of any value/ data/ number, we can apply the various formulas as discussed above as per the condition applied. Let us learn the basic method to find the percentage.

A% of a data = B
Here B is the necessary percentage.
If we wish to remove the % sign, then the formula is expressed as:
A/100 * given data = B
For example: How to calculate 20% of 60.
Let 20% of 60 = Y
20/100 * 60 = Y
Y = 12

Similarly; 8% means 8 out of every 100, or in fraction we write 8/100.
In the same way, 50% can be composed as a fraction, 1/2, or a decimal, 0.5.

Percentage Table

How to Convert Fractions to Percentages?

A fraction can be represented by x/y  and can be converted into percentage by the below formula: x/y * 100

Therefore by the formula, it is clear that we can convert fraction to percentage merely by multiplying the given fraction by 100.

Note: To convert percentages into fraction, divide it by 100.
Example: 25% = 25/100 = ¼
To convert a fraction into percentage, multiply in by 100.

Difference between Percentage and Percent

• The terms percentage and percent are closely related.
•  The use of percent (or the symbol %) is always paired with a specific number.
• On the other hand, percentage is used without a number.
•  Example of percent: 
  • More than 65% of the country's population has received the first dose of the Covid-19 vaccine.
• Example of percentage:
  •  A very large percentage of the world's population has been affected by the Covid-19 pandemic.