Boats & Streams
Boats and Streams is a fundamental topic in Quantitative Aptitude that builds upon the basic concepts of Speed, Distance, and Time. In this topic, we study how the movement of water affects the speed of an object moving through it. There are two main components: the object (usually a boat or a person swimming) and the medium (the water or stream). When we say 'Still Water,' we mean water that is not moving at all, like in a pond or a swimming pool.
Concepts (3)
Downstream speed occurs when the boat moves in the direction of the river. The water helps the boat move faster. For example, if a boat's speed is 10 km/h and the river speed is 3 km/h, the downstream speed is 13 km/h.
Downstream speed occurs when the boat moves in the direction of the river. The water helps the boat move faster. For example, if a boat's speed is 10 km/h and the river speed is 3 km/h, the downstream speed is 13 km/h. This is the fastest the boat can travel with its current effort.
Sometimes the exam gives you only the downstream and upstream speeds. You must find the individual speeds. To find the boat's speed, you add the two speeds and divide by two.
Sometimes the exam gives you only the downstream and upstream speeds. You must find the individual speeds. To find the boat's speed, you add the two speeds and divide by two. To find the stream's speed, you subtract the smaller speed from the larger one and divide by two.
Upstream speed occurs when the boat moves against the flow of the river. The water pushes against the boat, slowing it down. For example, if a boat's speed is 10 km/h and the river speed is 3 km/h, the upstream speed is only 7 km/h.
Upstream speed occurs when the boat moves against the flow of the river. The water pushes against the boat, slowing it down. For example, if a boat's speed is 10 km/h and the river speed is 3 km/h, the upstream speed is only 7 km/h. The boat must be faster than the stream to move forward.
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Start Lesson: Downstream Speed