Ex - 9.2, Ratio And Proportion, Class 7, Math RD Sharma Solutions | RD Sharma Solutions for Class 7 Mathematics PDF Download

Question 1:

Which ratio is larger in the following pairs?
 (i) 3 : 4 or 9 : 16
 (ii) 15 : 16 or 24 : 25
 (iii) 4 : 7 or 5 : 8
 (iv) 9 : 20 or 8 : 13
 (v) 1 : 2 or 13 : 27

Answer 1:

(i) Writing the ratios as fractions, we have
        3 : 4 = 3/4 and 9 : 16 = 9/16
     Now, LCM of 4 and 16 = 16.
     Making the denominator of each fraction = 16, we have

 and the other fraction = 9/16

Of 12/16 and 9/16,  clearly  

therefore, 

Writing the ratios as fractions, we have
        15 : 16 = 15/16 and 24 : 25 = 24/25
     Now, LCM of 16 and 25 = 400.
     Making the denominator of each fraction = 400, we have

 and the other fraction = 

Clearly, 384 > 375. So, 

 Therefore,  

(iii) Writing the ratios as fractions, we have
        4 : 7 = 4/7 and 5 : 8 = 5/8
     Now, LCM of 7 and 8 = 56.
     Making the denominator of each fraction = 56, we have

 and the other fraction =

Clearly, 36 > 32. So,

Therefore, 

(iv) Writing the ratios as fractions, we have
       9 : 20 = 9/20 and 8 : 13 = 8/13
     Now, LCM of 20 and 13 = 260.
     Making the denominator of each fraction = 260, we have

 and the other fraction =   

Clearly, 160 > 117. So,

 Therefore, 

(v) Writing the ratios as fractions, we have
       1 : 2 = 1/2 and 13 : 27 = 13/27
     Now, LCM of 2 and 27 = 54.
     Making the denominator of each fraction = 54, we have

 and the other fraction =

Clearly, 27 > 26. So,  

Therefore, 

Question 2:

Give two equivalent ratios of 6 : 8.

Answer 2:

We have

Therefore, 3 : 4 is an equivalent ratio of 6 : 8.

Hence, 3 : 4 and 12 : 16 are equivalent ratios of 6 : 8.

Question 3:

Fill in the following blanks:  

Answer 3: