P, Q and R are partners sharing profits in the ratio of 5 : 4 : 3. Q retires and P and R decide to share future profits equally. Gaining Ratio will be :

1:3

The correct answer is option 2- 1:3.

Old ratio is 5:4:3 (P, Q and R)
Q retires
New ratio is 1:1 (P and R)

GAINED SHARE = NEW SHARE - OLD SHARE

Gain of P = 1/2 - 5/12
               = (6-5)/12
               = 1/12

Gain of R = 1/2 - 3/12
               = (6-3)/12
               = 3/12

Gaining ratio is = 1/12:3/12
                        = 1:3