Page 109 - Maths Class 06

The unlike fraction can be converted into like fractions by using the concept of equivalent fractions.
Comparison of Fractions

a. Frac tions with same de nom i na tor : When we com pare two frac tions with the same de nom i na tor, the
frac tion with the greater nu mer a tor is greater.

3 1
e g. ., >
5 5

b. Frac tion with same nu mer a tor : When we com pare two frac tions with the same nu mer a tor, the frac tion
with the greater de nom i na tor is smaller.

1 1
e g. ., >
2 3
c. Frac tions with dif fer ent nu mer a tor and de nom i na tor : Us ing the con cept of equiv a lent frac tions, make
the de nom i na tors of the given re spec tive frac tions equal and then com pare us ing (a).

NOTE

To compare mixed fractions, express them as improper fractions and then proceed.

Addition and Subtraction of Fractions

a. Ad di tion and sub trac tion of like frac tions : To find the sum (dif fer ence) of the frac tions with the same
de nom i na tors, sim ply add (sub tract) the nu mer a tors, re tain the de nom i na tor as it is and form the
1 5
re quired frac tion, e g. . let us add ,
11 11
1 5 ( 1 5+ ) 6
+ = =
11 11 11 11
2 7
Let us subtract from
5 5
7 2 (7 - )2 5
- = = = 1
5 5 5 5
b. Addition and subtraction of unlike frac tions : To find the sum (difference) of the fractions with
dif fer ent de nom i na tors, make the de nom i na tors same by tak ing their LCM of de nom i na tors and pro ceed
1 5
as above, e g. ., let us add , .
4 6
LCM of 4 and 6 is 12 and 12 4¸ = 3 ; 12 6¸ = 2
1 1 3´ 3 5 5 ´2 10
= = , = =
4 4 3´ 12 6 6 ´2 12

1 5 3 10 13
Thus, + = + =
4 6 12 12 12
2 8
Let us subtract from
7 3

LCM of 7 and 3 is 21 and 21 7¸ = 3; 21 3¸ = 7

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