A and B share profits in the ratio of 3:2. C was admitted as a partner who gets 1/5 share. New profit sharing ratio, if C acquires 3/20 from A and 1/20 from B, would be:

9:7:4

The correct answer is option 1- 9:7:4.

A and B old ratio = 3:2
C admits = 1/5 share
C acquires 3/20 from A and 1/20 from B
So, sacrificing ratio = 3/20 : 1/20 
                             = 3:1

New share = Old share - Sacrificed share

New share of A = 3/5 - 3/20
                       = (12-3)/20
                        = 9/20

New share of B = 2/5 - 1/20
                       = (8-1)/20
                       = 7/20

New ratio = 9/20 : 7/20 : 1/5
               = 9/20 : 7/20 : 4/20
               = 9:7:4