A motorboat travels 180 km in 3 hours going upstream and 504 in 6 hours going downstream. What is the rate of the boat in still water and what is the rate of the current?
Accepted Solution
A:
Answer:Speed of boat x = 84 km/hrSpeed of current = 12 km/hrStep-by-step explanation:Let 'x' be the speed of boat and 'y' be the speed of still waterUpstream speed = x - y and Downstream speed = x + yIt is given that, A motorboat travels 180 km in 3 hours going upstream and 504 in 6 hours going downstreamUpstream speed = x - y = 180/3 = 60 km/hrDownstream speed = x + y = 504/6 = 84 km/hrTo find the value of x and yx + y = 84 ----(1)x - y = 60 ----(2)(1) + (2) ⇒x + y = 84 ----(1)x - y = 60 ----(2)2x + 0 = 144x = 144/2 = 72x + y = 84y = 84 - 72 = 12Therefore speed of boat x = 84 km/hrSpeed of current = 12 km/hr