Pipes A and B together can fill an empty tank in 30 hours, whereas pipes B and C together can fill it in 24 hours. A, B and C together can fill the tank in 20 hours. In how many hours can pipe B alone fill 35% of the tank?
Joseph bought two woollen jackets for Rs. 2,100 and Rs. 3,150, respectively. By selling the first at a gain of k% and the second at a loss of k%, he found that the selling price of both is the same. What is the value of k?
A and B can complete a certain task in 24 days and 40 days, respectively. They worked together for 8 days. C completed the remaining task in 14 days. Working together, A and C will complete 75% of the same work in: