Introduction to Percentage

What is meant by percentage or percent?

Examples:

We use percentage all the time in our day-to-day life.
  • At the supermarket: 2% milk
  • In the mall: 70% off the price
  • A saying: Give it your 100%

The word "percent" is made up of 2 words - per and cent.
Let's first see what "cent" is.

$1  =  100 ¢ 
  =    1   
100th
  of a $

So,
percent  =    1   
100th
   =  1 part out of 100 parts
 
Similarly,
5 percent  =  5 parts out of 100 parts
Note:

We use % to denote percent.

So,
      1 percent  =  1%
      5 percent  =  5%



The basket of 100 balls



The above basket contains 100 balls of different colours.

There is 1 black ball.
What percentage of balls in the basket is black?

Black ball  =  1 out of 100
   =  1%
So, 1% of balls in the basket is black.


There are 10 blue balls.
What is the percentage of blue balls in the basket?

Blue balls  =  10 out of 100
   =  10%
So, the basket contains 10% blue balls.


21% of balls in the basket are yellow.
How many yellow balls are there?

Yellow balls  =  21%
   =  21 out of 100
So, there are 21 yellow balls.


The basket contains 100 objects all of which are balls.
What percent of the objects in the basket are balls?

Balls  =  100 out of 100 objects
   =  100%
So, 100% of the objects in the basket are balls.