A is working, and B a sleeping partner in a business. A puts in Rs.12000 and B Rs. 20000. A receives 10% of the profit for managing, the rest being divided in proportion to their capitals. Out of a total profit of Rs. 9600, the money received by A will be

Given information : 
Capital of A = 12,000
Capital of B = 20,000
                                Hence, the ratio of investments for A is to B = 3:5

Total profit given as = 9600

As "A" is managing the business , he is being paid = (0.1)(9600) = 960
So, the remaining profit = 9600-960 = 8640

This remaining has to be shared in proportion of investment : A's share = $$\dfrac{\ 3}{8}\left(8640\right)$$ = 3240
                                                                                             B's share = $$\dfrac{\ 5}{8}\left(8640\right)$$ = 5400

Therefore, total earning of A = 3240 + 960 = 4200