1.
In a stream running at 2 km/h, a motor boat goes 10 km upstream and back again to the starting point in 55 min. Find the speed of the motorboat in still water.
- A.20 km/h
- C.24 km/h
- B.22 km/h
- D.21 km/h
- Answer & Explanation
- Report
Answer : [B]
Explanation :
Explanation :
| Let the speed of the motorboat in still water be x km/h | |||||||||||||
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| So, x = 2 km/h (neglecting the negative value) | |||||||||||||
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2.
A man can row 6 km/h in still water. If the river is running at 2 km/h, it takes 3 hours more in upstream than to go downstream for the same distance. How far is the place?
- A.36 km
- C.28 km
- B.24 km
- D.None of these
- Answer & Explanation
- Report
Answer : [B]
Explanation :
Explanation :
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3.
Two boats, traveling 5 and 10 km/h, head directly towards each other. They begin at a distance of 20 kms from each other. How far apart are they (in kms) one minute before they collide?
- A.1/3
- C.1/4
- B.1/6
- D.1/12
- Answer & Explanation
- Report
Answer : [C]
Explanation :
Explanation :
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4.
A boat goes 13 km upstream in 39 minutes. The speed of stream is 3 km/h. The speed of boat in still water is
- A.27 km/h
- C.23 km/h
- B.25 km/h
- D.None of these
- Answer & Explanation
- Report
Answer : [C]
Explanation :
Explanation :
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| Speed of the stream = 3 km/h | |||||
| Let the speed of the boat in still water = x km/h | |||||
| We have, x – 3 = 20 | |||||
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5.
A motor went the river for 14 km and then up the river for 9 km. It took a total of 5 hours the entire journey. Find the speed of the river flow if the speed of the boat in still water is 5 km/h.
- A.3 km/h
- C.2 km/h
- B.1.5 km/h
- D.1 km/h
- Answer & Explanation
- Report
Answer : [C]
Explanation :
Explanation :
| Let the speed of the stream be x km/hours | |||||||||||
| Then Upward speed = (5 – x) km/h and Downward speed = (5 + x) km/h | |||||||||||
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