CLASS-8
COMPARISON OF FRACTION

Comparison of Fraction

Among the like fraction, the fraction with the greatest numerator is the greatest, to compare, unlike fraction we first convert them into like fractions and then compare their numerator.

Example.1)                5        7        11

Arrange the fraction, ------, ------, ------ in ascending order.

                           18       42       72

Answer) To change the given fraction first we have to find the LCM of the denominators.

So, LCM of the denominator would be –

LCM of the denominator of respective fraction, is = 2 X 3 X 3 X 7 X 4 = 504   

Now, we will find the factor via division of obtained LCM by denominator of given Fraction respectively,

so we find –

504 ÷ 18 =  28,  504 ÷ 42 = 12 ,  504 ÷ 72 = 7

Now, we will multiply obtain factor to both numerator & denominator respectively and we find –

     5           5 X 28           140

-------- = ----------- = ---------

    18          18 X 24          504

                                                              

    7           7 X 12            84

------- = ----------- =  ---------

   42          42 X 12           504

 

    11           11 X 7           77

-------- = ----------- = ---------

    72           72 X 7          504

 

           140           84           77

Hence, --------,  --------,  --------

           504          504          504

Now, if we compare the numerator of the obtained fraction, then we find   77 < 84 < 140

         77           84          140

So, -------- < -------- < --------

        504          504          504

Hence, the fractions in ascending order would be -

          11           7             5

So,   ------- < -------- < --------

          72          42            18