P can do a work in the same time in which Q and R together can do it. If P and Q work together, the work can be completed in 10 days. R alone needs 50 days to complete the same work. then Q alone can do it in
Two trains of equal length are running on parallel lines in the same directions at 46 km/hr and 36 km/hr and 36 km/hr. the faster train passes the allower train in 36 sec. the length of each train is
Two train 200 m and 150 m long are running on parallel rails at the rate of 40 kmph and 45 kmph respectively. In how much time will they cross each other, if they are running in the same direction
2 trains starting at the same time from 2 stations 200km apart and going in opposite direction cross each other at a distance of 110km from one of the stations. What is the ratio of their speeds?
Speed of a boat in standing water is 9km ph and the speed of the stream is 1.5km ph. A man rows to a place at a distance of 105km and comes back to the starting point. The total time taken by him is