Question

A man rows a boat at a speed of 5 km / hr in still water. Find 1the speed of a river if it takes him 1 hr to row a boat to a place 2.4 km away and return

Answer 1

Answer:

1 km/hr

Step-by-step explanation:

one side Distance = 5 km

Let say speed of river = x km/hr

Speed with Stream = 5 + x  km /hr

Speed against stream =  5 - x km/hr

Total time taken = 1 hr

Total Time  =  (2.4)/(5+x)   +  (2.4)/(5-x)  = 1

(2.4)(5-x + 5 + x) = (5+x)(5-x)

2.4 * 10 = 5^2  - x^2)

24 = 25 - x^2

x^2 = 1  

x = 1 km/hr

Answer 2

Answer:

Step-by-step explanation: