Chapter
10
Fractions
Recognising Equivalent Fractions
Thinking Platform
Look at the problems below.
Problem 1
Amanda and Eugene bought 2 identical pizzas.
1
1
Amanda ate of her pizza and Eugene ate
2
4
of his pizza.
Think! Who ate a bigger portion of their pizzas?
Problem 2
Amanda and Eugene bought 2 identical pizzas.
1
2
Amanda ate of her pizza and Eugene ate
2
4
of his pizza.
Note s
Think! Did Eugene eat more of his pizza than
Amanda did in Problem 2? Why?
Teaching Tips
In this chapter, we will first introduce the concept of equivalent fractions pictorially, before delving into the method
of making the numerator or the denominator the same.
In the two problems above, the key word is the term ‘identical’. Two fractions must come from similar or the same
whole, before we can then proceed to compare and order them.
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Let us represent the fractions in Problem 1 using rectangular bars.
The shaded parts show the portion of the pizzas they have eaten.
Amanda
Eugene
We can easily see that Amanda ate a bigger portion compared to Eugene.
1
1
Therefore, we can conclude that is greater than .
2
4
Let us do the same for Problem 2.
Amanda
Eugene
The bars clearly show that Amanda and Eugene ate portions of similar size.
1
2
Therefore, we can conclude that is equal to .
2
4
We say that 1 and 2 are equivalent fractions.
2
4
1
1
Think! Can you think of a scenario where is greater than ?
4
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Simplifying Fractions
Thinking Platform
Look at the following equivalent fraction.
4
=
12
?
9
Think! Can you identify the missing number?
What number should you multiply with the numerator and the
denominator to obtain the equivalent fraction?
To find the missing number, we must first simplify
4
.
12
Fractions can be reduced to their simplest form by dividing the numerator and
denominator by the same number.
We can also use this method to find equivalent fractions.
4
4÷4
1
=
=
12 12 ÷ 4 3
4
12
1
3
Therefore, we can conclude that
4
1
can be simplified to .
12
3
Now, we are able to find the equivalent fraction.
1
1×3 3
=
=
3 3×3 9
4
12
1
3
3
9
Therefore, we can conclude that
4
3
and are equivalent fractions.
12
9
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Summative Test
Multiple-Choice Questions
Write the number of the correct answer in the brackets.
1. What fraction of the figure below is shaded?
1
4
(1)
(2) 3
(3) 5
(4) 1 8
8
2
(
)
(
)
(
)
2. Which one of the following fractions is the smallest?
3
10
(1)
(2) 1
(3) 2
(4) 5 2
3
12
3. What is the sum of A and B in the equation below?
8
= A = 10
12 9
B
(1)
(2)
(3)
(4)
6
9
15
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