IBPS Clerk Prelims 12-Dec-2020 Shift 2 Paper

Two boats P and Q travels downstream from A to B. The ratio of time taken to cover the distance from A to B by both boat is 4 : 5. If speed of boat Q is 34 km/h and speed of stream is 6 km/h, what will be the speed of  boat P, when it travel from B to A?