Q. A boat travels 50 km downstream in 5 hours. If the speed of the current is 5 km/h, what is the speed of the boat in still water?
A.
8 km/h
B.
10 km/h
C.
12 km/h
D.
14 km/h
Solution
Speed downstream = Distance/Time = 50 km / 5 h = 10 km/h. Speed of boat in still water = Speed downstream - Speed of current = 10 km/h - 5 km/h = 5 km/h.
Q. A boat travels 60 km downstream in 3 hours. If the speed of the current is 6 km/h, what is the speed of the boat in still water?
A.
18 km/h
B.
20 km/h
C.
22 km/h
D.
24 km/h
Solution
Speed downstream = Distance/Time = 60 km / 3 h = 20 km/h. Speed of boat in still water = Speed downstream - Speed of current = 20 km/h - 6 km/h = 14 km/h.
Q. If a boat can travel 20 km downstream in 1 hour, what is the speed of the boat in still water if the speed of the current is 4 km/h?
A.
12 km/h
B.
16 km/h
C.
20 km/h
D.
24 km/h
Solution
Speed downstream = Distance/Time = 20 km / 1 h = 20 km/h. Speed of boat in still water = Speed downstream - Speed of current = 20 km/h - 4 km/h = 16 km/h.
Q. If a boat can travel 50 km downstream in 2 hours, and the speed of the current is 5 km/h, what is the speed of the boat in still water?
A.
20 km/h
B.
25 km/h
C.
30 km/h
D.
35 km/h
Solution
Speed downstream = Distance/Time = 50 km / 2 h = 25 km/h. Speed of boat in still water = Speed downstream - Speed of current = 25 km/h - 5 km/h = 20 km/h.
Q. If a boat can travel 60 km downstream in 4 hours, what is the speed of the current if the speed of the boat in still water is 15 km/h?
A.
3 km/h
B.
4 km/h
C.
5 km/h
D.
6 km/h
Solution
Speed downstream = Distance/Time = 60 km / 4 h = 15 km/h. Speed of current = Speed downstream - Speed of boat in still water = 15 km/h - 15 km/h = 0 km/h.
