Question

Two boats go downstream from point X to point Y. The faster boat covers the distance from X to Y 1.5 times as fast as the slower boat. It is known that for every hour the slower boat lags behind the faster boat by 8 km. However if they go upstream then the faster boat covers the distance from Y to X in half the time as the slower boat. Find the speed of the slower boat in still water?

Answer 1

Answer:

the speed of the slower boat in still water = 12 km/Hr

Step-by-step explanation:

Let say Speed of Faster Boat = F km/hr

Speed of Slower Boat = X km/Hr

Speed of stream = S km /hr

Speed of Faster Boat during downstream = F + S km/hr

Speed of Slower Boat during downstream = X + S km/hr

F + S = 1.5 ( X + S)

F + S - X + S = 8

=> F = X + 8

X + 8 + S = 1.5 ( X + S)

=> X + 8 + S = 1.5X + 1.5S

=> 0.5 X + 0.5S = 8

=> X + S = 16

Upstream speeds

F -S   & X - S

F-S = 2(X -S)

=> F - S = 2X - 2S

=> F + S = 2X

=> X + 8 + S = 2X

=> X - S = 8

Adding both equation

2X = 24

X = 12 km/hr

the speed of the slower boat in still water = 12 km/Hr