Quiz Discussion

A boat moves downstream at the rate of 1 km in \({ \text{7}}\frac{1}{2}\) minutes and upstream at the rate of 5 km an hour. What is the speed of the boat in the still water?

• 1]

  8 km/hour

• 2]

  \({ \text{6}}\frac{1}{2}\) km/hour

• 3]

  4 km/hour

• 4]

  \({ \text{3}}\frac{1}{2}\) km/hour

A man's speed with the current is 15 km/hr and the speed of the current is 2.5 km/hr. The man's speed against the current is:

• 1]

  8.5 km/hr

• 2]

  9 km/hr

• 3]

  10 km/hr

• 4]

  12.5 km/hr

The speed of a boat along the stream is 12 km/hr and against the stream is 8 km/hr. The time taken by the boat to sail 24 km in still water is?

• 1] 2 hrs
• 2] 3 hrs
• 3] 2.4 hrs
• 4] 1.2 hrs

A man row to a place 48 km distant and back on 14 hours text. He finds that he can row 4 km with the stream in the same time as 3 km against the stream. The rate of the stream is?

• 1] 1 km/hr
• 2] 1.5 km/hr
• 3] 1.8 km/hr
• 4] 3.5 km/hr

A boat can travel with a speed of 13 km/hr in still water. If the speed of the stream is 4 km/hr, find the time taken by the boat to go 68 km downstream.

• 1]

  2 hours

• 2]

  3 hours

• 3]

  4 hours 

• 4]

  5 hours

A motorboat, whose speed in 15 km/hr in still water goes 30 km downstream and comes back in a total of 4 hours 30 minutes. The speed of the stream (in km/hr) is:

• 1]

  4

• 2]

  5

• 3]

  6

• 4]

  10

The speed of a boat in still water in 15 km/hr and the rate of current is 3 km/hr. The distance travelled downstream in 12 minutes is:

• 1] 1.2 km
• 2] 1.8 km
• 3] 2.4 km
• 4] 3.6 km
• 5] None of these

A boat takes half time in moving a certain distance downstream than upstream. The ratio of the speed of the boat in still water and that of the current is?

• 1] 2 : 1
• 2] 4 : 3
• 3] 1 : 2
• 4] 3 : 1

Speed of a along and against the current are 14 kms/hr and 8 kms/hr respectively. The speed of the current is?

• 1] 11 km/hr
• 2] 6 km/hr
• 3] 5.5 km/hr
• 4] 3 km/hr

A man can row at 8 kmph in still water. If the river is running at 2 kmph, it takes him 48 minutes to row to a place and back. How far is the place?

• 1]

  1 Km

• 2]

  2 Km

• 3]

  3 Km

• 4]

  4 Km