FRACTIONS

COMBINED OPERATIONS ON FRACTIONS

BACKGROUND KNOWLEDGE

1. Identify proper, improper fractions and mixed numbers. 

for example is a proper fraction

is an improper fraction

is a mixed number (1 is a whole number

and is a proper fraction)

2. Converting mixed numbers to improper fractions and vice

versa.

for example converted to be which is a proper 

fraction.

is converted to be which is a mixed number.

3. Comparing fractions.

We compare fractions by using the LCM.

Write the following fractions in the ascending order.

, , , 

In order to arrange these fractions in ascending order we

find the LCM of the denominators

4, 3, 7, 5

4 3 7 5

2 2 3 7 5

2 1 3 7 5

3 1 1 7 5

5 1 1 7 1

7 1 1 1 1

2 x 2 x 3 x 5 x 7= 420

= ; = ; = ; = 

Therefore , , , 

, , ,

Arranging them in ascending order we get:

, , , 

Or

, , ,

Recalling the four basic operations involving

factorizations that are addition, subtraction,

and multiplication and division e.g:

a). +

b). -

c). X

d). -