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 boat while dowenstream in a reiver converd a distance of 50 miles at an average speed of 60 miles per hour. While returning , because of the water resistance , it took 1 hour 15 minutes to cover the same distance What was the average speed during the whole journey?

• 1] 40 mph
• 2] 48 mph
• 3] 50 mph
• 4] 55 mph

A boat can tarvel 36 km upstream in 5 hours. If the speed of the stream is 2.4 kmph, how much time will the boat take to cover a distance of 78 km downstream?(in hours)

• 1] 5 hours
• 2] 6.5 hours
• 3] 5.5 hours
• 4] 8 hours

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 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

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 km/hr

• 2]

  5 km/hr

• 3]

  8 km/hr

• 4]

  9 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
• 5] None of these

A man takes 2.2 times as long to row a distance upstream as to row the same distance downstream. If he can row 55 km downstream in 2 hour 30 minutes, what is the speed of the boat in the still water?

• 1] 40 km/h
• 2] 8 km/h
• 3] 16 km/h
• 4] 24 km/h

A man rows to a place 48 km distant and come back in 14 hours. 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] 2 km/hr
• 4] 2.5 km/hr

A man can row at 5 kmph in still water. If the velocity of current is 1 kmph and it takes him 1 hour to row to a place and come back, how far is the place?

• 1] 2.4 km
• 2] 2.5 km
• 3] 3 km
• 4] 3.6 km
• 5] None of these