Page 77 - Maths Class 05

Example : Express the following fractions in their simplest form.

6 18 210
a. b. c.
8 30 330

Solution : a. Divide both numerator and denominator by the HCF.

Factors of 6 are 1, 2, 3, 6
2 is the HCF of 6 and 8.
Factors of 8 are 1, 2, 4, 8

Dividing 6 and 8 by 2, we have,

6 6 ÷ 2 3
= = ( 3 and 4 have no common factor except 1.)
8 8 ÷ 2 4
\
18 18 ÷ 6 3
b. = = ( 6 is the HCF of 18 and 30.)
\
30 30 ÷ 6 5
3 18
Hence, is the simplest form of because 3 and 5 have no
5 30

common factor except 1.

Alternative Method

To reduce a fraction to its simplest form, keep dividing by common

factors until the only common factor is 1.

7
35 Think!
105
210 210 7 Start dividing by the least common
c. = =
330 330 11 factor. First divide by 2, then by 3
165 and lastly by 5.
55
11

Carry On

Reduce the following fractions to their lowest term :

1. 16 = 2. 60 = 3. 84 = 4. 55 =
18 105 98 70

Mathematics-5 77