Page 111 - Start Up Mathematics_4

8. Write the equivalent fractions with denominator 40.
2 3 1 5 7 11
(a) (b) (c) (d) (e) (f)
5 10 4 2 8 20

Types of Fractions

Like fractions: Fractions that have the same denominator are called like fractions.
2 3 4
For example, , and are like fractions.
5 5 5
Unlike fractions: Fractions that have different denominators are called unlike fractions.
2 9 3
For example, , and are unlike fractions.
5 2 7
We can change unlike fractions to like fractions by multiplying the numerator and denominator
of one fraction by the denominator of the other fraction.
2 7
Example 7: Convert and to like fractions.
5 3
2 2 × 3 6 7 7 × 5 35
Solution: = = = =
5 5 × 3 15 3 3 × 5 15
6 35
and are the required like fractions.
15 15
Proper fractions: Fractions in which the numerator is less than the denominator are called
proper fractions.
2 3 7 13 1
For example, , , , and are proper fractions.
5 6 11 18 3
Improper fractions: Fractions in which the numerator is greater than the denominator are
called improper fractions.
7 5 7 12 11
For example, , , , and are improper fractions.
2 3 5 9 6
Unit fractions: Fractions in which the numerator is 1 are
called unit fractions. Remember
1 1 1 1 1 1
For example, , , and are unit fractions. • 3 means 3 + .
5 7 6 4 2 2
Mixed fractions: Fractions which are made up of a whole • Only improper fractions
can be changed into
number and a proper fraction are called mixed fractions. mixed fractions.
1 3 4
For example, 3 , 5 and 6 are mixed fractions.
2 4 7

Quick Tip
If N is the numerator and D is the denominator, then:
• Like fractions: same D • Unlike fractions: different D
• Proper fractions: N < D • Improper fractions: N > D

• Unit fractions: N = 1 • Mixed fractions: Whole number + N
D

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