Percentage Calculations 2

1
Percentages from Fractions
2
(No Transcript)
3
Non Calculator
Percentages from Fractions
Remember A percentage is simply a fraction out
of 100.
Percentages from simple fractions without a
calculator.
Example 1 What
percentage of the grid is coloured pink?
Simply find the fraction that is coloured pink
then find the equivalent fraction out of 100.
60
4
Percentages from Fractions
Remember A percentage is simply a fraction out
of 100.
Percentages from simple fractions without a
calculator.
Example 2 What
percentage of the grid is coloured red?
Simply find the fraction that is coloured red
then find the equivalent fraction out of 100.
40
5
Percentages from Fractions
Remember A percentage is simply a fraction out
of 100.
Percentages from simple fractions without a
calculator.
Example 3 What
percentage of the grid is coloured blue?
Simply find the fraction that is coloured blue
then find the equivalent fraction out of 100.
30
6
Percentages from Fractions
Remember A percentage is simply a fraction out
of 100.
Percentages from simple fractions without a
calculator.
Example 4 What
percentage of the discs are coloured red?
Simply find the fraction that is coloured red
then find the equivalent fraction out of 100.
60
7
Percentages from Fractions
For each of the following diagrams, calculate the
percentage for the coloured indicated. You may
well be able to do this in your head.
red
green
silver
pink
blue
45
70
44
80
75
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Calculator
Percentages from Fractions
Remember A percentage is simply a fraction out
of 100.
Percentages from fractions using a calculator.
Example 1 What
percentage of the grid is coloured pink?
Simply find the fraction that is coloured pink,
then multiply it by 100.
9
1
5
x
1
0

0
60
9
Percentages from Fractions
Remember A percentage is simply a fraction out
of 100.
Percentages from fractions using a calculator.
Example 2 What
percentage of the toys are soldiers?
Simply find the fraction that are soldiers, then
multiply it by 100.
3
8
x
1
0

0
37.5
10
Percentages from Fractions
Remember A percentage is simply a fraction out
of 100.
Percentages from fractions using a calculator.
Example 3 What
percentage of the toys are teddies? (1 dp)
Simply find the fraction that are teddies, then
multiply it by 100.
5
1
2
x
1
0

0
41.7
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Percentages from Fractions
For each of the cases below, find the required
percentage (1 dp)
3D shapes
blue balls
ducks
red squares
58.3
26.7
38.9
44.4
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Why x 100?
Percentages from Fractions
Remember A percentage is simply a fraction out
of 100.
Percentages from fractions using a calculator.
Why do we multiply by 100?
We do this in order to turn the first part of a
calculation from a decimal to a percentage.
5
1
2
x
1
0

0
41.7
13
Percentages from Fractions
For each of the following diagrams, calculate the
percentage for the coloured indicated. You may
well be able to do this in your head.
red
green
silver
pink
blue
14
Percentages from Fractions
For each of the cases below, find the required
percentage (1 dp)
3D shapes
blue balls
ducks
red squares