$$\text{A, B,}$$ and $$\text{C}$$ start a business with investments in the ratio $$3 : 4 : 6$$. After $$6$$ months, $$\text{A}$$ doubles his investment, $$\text{B}$$ withdraws $$25\%$$ of his investment, and $$\text{C}$$ keeps his investment unchanged. If the total profit at the end of a year is $$\text{Rs. } 64,400$$, what is $$\text{B}$$'s share in the profit?
A) $$\text{Rs. } 16,100$$
B) $$\text{Rs. } 27,600$$
C) $$\text{Rs. } 20,700$$
D) $$\text{Rs. } 18,400$$
Explanation:
Let the initial investments of $$\text{A, B,}$$ and $$\text{C}$$ be $$3x, 4x,$$ and $$6x$$ respectively.
Calculate the capital-time product for $$12$$ months for each partner:
1. <b>For $$\text{A}$$:</b> $$(3x \times 6) + (6x \times 6) = 18x + 36x = 54x$$.
2. <b>For $$\text{B}$$:</b> After withdrawing $$25\%$$, remaining capital $$= 4x \times 0.75 = 3x$$.
Total for $$\text{B}$$ $$= (4x \times 6) + (3x \times 6) = 24x + 18x = 42x$$.
3. <b>For $$\text{C}$$:</b> $$6x \times 12 = 72x$$.
Ratio of profits $$A : B : C = 54x : 42x : 72x = 9 : 7 : 12$$.
Total ratio units $$= 9 + 7 + 12 = 28\text{ units}$$. $$\text{B}$$'s share in the profit $$= \left(\frac{7}{28}\right) \times 64,400 = \frac{1}{4} \times 64,400 = \text{Rs. } 16,100$$.