Quiz Discussion

A man can row at a speed of \(4\frac{1}{2}\) km/hr in still water. If he takes 2 times as long to row a distance upstream as to row the same distance downstream, then the speed of stream (in km/hr) is-

• 1] 1
• 2] 1.5
• 3] 2
• 4] 2.5

A motorboat in still water travels at a speed of 36 km/hr. It goes 56 km upstream in 1 hour 45 monutes. The time taken by it to cover the same distance down the stream will be-

• 1] 1 hour 24 minutes
• 2] 2 hour 21 minutes
• 3] 2 hour 25 minutes
• 4] 3 hour

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 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

Speed of a boat in standing water is 9 kmph and the speed of the stream is 1.5 kmph. A man rows to a place at a distance of 105 km and comes back to the starting point. The total time taken by him is:

• 1] 16 hours
• 2] 18 hours
• 3] 20 hours
• 4] 24 hours

The speed of a boat downstream is 15 km/hr and the speed of current is 3 km/hr. Find the total time taken by the boat to cover 15 km upstream and 15 km downstream.

• 1] 2 hours 40 minutes
• 2] 2 hours 42 minutes
• 3] 2 hours 10 minutes
• 4] 2 hours 30 minutes

A man rows 12 km in 5 hours against the stream and the speed of current being 4 kmph. What time will be taken by him to row 15 km with the stream?

• 1]

  1 hour \({ \text{27}}\frac{7}{{13}}\) minutes

• 2]

  1 hour \({ \text{24}}\frac{7}{{13}}\) minutes

• 3]

  1 hour \({ \text{25}}\frac{7}{{13}}\) minutes

• 4]

  1 hour \({ \text{26}}\frac{7}{{13}}\) minutes

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 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 km/hr
• 2] 5 km/hr
• 3] 6 km/hr
• 4] 10 km/hr

In one hour, a boat goes 11 km/hr along the stream and 5 km/hr against the stream. The speed of the boat in still water (in km/hr) is:

• 1] 3 kmph
• 2] 5 kmph
• 3] 8 kmph
• 4] 9 kmphr