Page 66 - Start Up Mathematics_5

4 Fractions—Addition

and Subtraction

Let’s Recall ...

• A fraction is a part of a whole or a collection.

• Equivalent fractions have the same value or represent the same part of a
1 2 4
whole. For example, , ,
2 4 8
9 4 6
• Fractions that have the same denominator are called like fractions. For example, , ,
3 3 3
• Fractions that have different denominators are called unlike fractions. For example,
2 5 9
, ,
3 2 4
• Fractions in which the numerator is less than the denominator are called proper fractions.
3 2 1
For example, , ,
5 7 4
• Fractions in which the numerator is greater than the denominator are called improper
8 9 3
fractions. For example, , ,
5 7 2
1 1
• Fractions in which the numerator is 1 are called unit fractions. For example, ,
3 7
• Mixed fractions are made up of a whole number and a proper fraction. For example,
3
1
2 , 4 , 9 1
3 5 2
• To convert a mixed fraction to an improper fraction, use the given formula:
(Whole number × Denominator) + Numerator
Improper fraction =
Denominator
• To convert an improper fraction to a mixed fraction, use the given formula:

Remainder
Mixed fraction = Quotient
Divisor
• We can compare and arrange fractions by converting them into like fractions. For
3
2
example, > > 1
4 4 4
• A fraction is said to be in its lowest term when its numerator and denominator have
3 5 7
only 1 as the common factor. For example, , ,
2 4 3
1 Write three equivalent fractions for 9 . Is it equivalent to 5 ?
11 33

2 Convert to mixed fractions.

(a) 21 (b) 17 (c) 25 (d) 58 (e) 37 (f) 89
11 4 8 9 5 13

58