A merchant purchased 650 kg of wheat at ₹50 per kg. He sold 250 kg of it at a profit of 24% and 200 kg at a loss of 24%. At what rate per kg (in ₹) should he sell the remaining wheat to gain 20% on his initial investment?
Working together, A, B and C can finish a piece of work in 3 hours. A finishes the same work in 8 hours and B finishes it in 6 hours. How long will it take for C alone to finish the same work?