Answer: C
Let B’s capital be \(x\) rupees. \(\therefore\) A’s capital : B’s capital = A’s profit : B’s profit i.e., \(600 : x = 90 : 60\) i.e., \(\cfrac{600}{x} = \cfrac{90}{60}\) i.e., \(90x = 600 \times 60\) i.e., \(x = \cfrac{600 \times 60}{90} = 400\) \(\therefore\) B’s capital is ₹400.
Let B’s capital be \(x\) rupees. \(\therefore\) A’s capital : B’s capital = A’s profit : B’s profit i.e., \(600 : x = 90 : 60\) i.e., \(\cfrac{600}{x} = \cfrac{90}{60}\) i.e., \(90x = 600 \times 60\) i.e., \(x = \cfrac{600 \times 60}{90} = 400\) \(\therefore\) B’s capital is ₹400.