The speed of a boat in still water is 15km/hr and the rate of current is
3 km/hr. the distance traveled downstream in 12 minutes is
3.0 km
4.6 km
3.6 km
6.9 km
Explanation:
Speed in still water = 15km/hr
½ (a+b) = 15km/hr
a+b = 30 km/hr -- (1)
speed of current = 3 km/hr
½ (a-b) = 3km/hr
a-b= 6 km/hr –(2)
1+2 è 2a = 36 è a=18 km/hr
ie., speed downstream = 18 km/hr
distance traveled downstream = 18 x 12/60 km = 3.6 km
Speed in still water = 15km/hr
½ (a+b) = 15km/hr
a+b = 30 km/hr -- (1)
speed of current = 3 km/hr
½ (a-b) = 3km/hr
a-b= 6 km/hr –(2)
1+2 è 2a = 36 è a=18 km/hr
ie., speed downstream = 18 km/hr
distance traveled downstream = 18 x 12/60 km = 3.6 km