In a class of 50 where the ratio of girls to boys is 3:2 . Sonika , a girl 30th from the top. If there are  16 girls ahead of her then, how many boys are after her?

6

Ratio of girls to boys is , 

         B  :  G

i.e.    2   :  3

Total number of students = 

  B = \(\frac{2}{5}\) × 50 = 20

 B= 20 ( number of boys) 

 G= 30 ( number of girls ) 

Now, 

Sonika is 30th from top and 15 girls are ahead of her . Till 30 there are 16 girls .

That means there are 14 boys ahead of her . 

So, number of boys after Sonika = total number of boys - number of boys ahead of her 

                                               = 20 - 14 = 6