R, S and K are partners sharing profits in the ratio of 4:3:2. R retires. S and K decided to share profits in the future in the ratio of 5:3. Gaining ratio of S and K will be:

21:11

The correct answer is Option (3) - 21:11.

Gaining share = New share - old share

Gain of S = 5/8 - 3/9
              = (45-24) / 72
             = 21/72

Gain of K = 3/8 - 2/9
              = (27-16) / 72
              = 11/72

Gaining ratio = 21/72 : 11/72
                     = 21:11