Page 183 - ICSE Math 5

Intr
Introduction to oduction to

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Percentageercentage
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Learning Outcomes

Students will be able to learn:
 about percentage and its pictorial representation.
 to relate fractions, decimals and percentages.
 to convert fractions to percentages and vice versa.
 to convert decimals to percentages and vice versa.
 to solve word problems on percentage.

In mathematics, percentage is a way of expressing a number as a fraction of 100. It is denoted
using a symbol ‘%’. The word per cent comes from a Latin word per meaning out of, and centum
1
meaning hundred. Thus, the meaning of per cent is out of hundred. For example, 1% means
100
or 1 out of hundred.
25 4
Example 1: Write (a) and (b) as percentage.
100 100
Remember
25
Solution: (a) = 25% (25 out of hundred) When we say per cent,
100 we mean per hundred.

  b 4 = 4% (4 out of hundred)
100

Pictorial Representation of Percentage

Now let’s understand what percentage means with the help of pictorial representation.

Look at the square grid shown below. There are 100 small squares in which some of the squares
are coloured. The coloured squares represent the percentage.

In the grid shown alongside, 50 out of 100 squares are coloured.
1
50
Thus, it can be written as in the fractional form which means
100
50% and is read as 50 per cent.
50
Similarly, we can represent 25%, 70% or 100% by colouring 25,

70 or 100 squares in the grid.

Mental Maths

100 1. What percentage of 30 is 15?
2. What percentage of 200 is 25?

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