CLASS-7
COMPARISON OF RATIO

Comparison of Ratio

Two ratios can be compared logically very easily if they have the same consequent (second term)

For Example –

We can compare 4:9 and 7:9 very easily because you can observe here, the denominator of that ratio are the same and now we have to compare only numerator, so we can observe that 7 > 4, so 4:9 < 7:9, 7:9 is greater than 4:9, this is the way we can compare the ratio.

There are some another way where we can compare, first we have to convert the ratio into fraction and we have to find the LCM of denominator first, for example –

We have to compare  4:9 and 7:15

So, first we have to convert the ratio into fraction –

              4              7

   d)    --------  :  ---------  

              9              15

Step.1) First we have to find out the LCM of both the denominator 9, 15             

Step.2) Now we will divide the obtained LCM by Denominator of given fraction respectively.

45 ÷ 9 = 5  and  45 ÷ 15 = 3 ; here 5 & 3 are the quotient respectively

Step.3)  Now, we will multiply by obtained quotient to denominator and numerator of the given fraction respectively

                4                4 X  5              20

We find   ---------  =  ------------  =  --------

                9                 9 X 5              45

 

                7                 7 X 3                21

We find   ---------  =   ------------  =  ---------

                15               15 X 3               45

 

          7              4              21            20

 So, --------- > --------- = --------- > --------     

          15             9              45            45


      =  4:9 < 7:15