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38.
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A
boatman goes 2 km against the current of the stream in 1 hour and goes 1 km
along the current in 10 minutes. How long will it take to go 5 km in
stationary water?
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A. 40 minutes
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B. 1 hour
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C.
1 hour 15 min
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D. 1 hour 30
min
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Answer:1 hour 15 min
Explanation:
Rate
downstream
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= (1
/ 10 x 60)km/hr
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= 6
km / hr.
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Rate
upstream
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= 2
km/hr.
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Speed
in still water
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= 1
/ 2(6 + 2)km/hr
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= 4
km.
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Required
time
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= (5
/ 4) km/hr
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= 1x
1/4 km/hr
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= 1
hr 15 min.
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Title : BOATS and STREAMS Q38
Description : 38. A boatman goes 2 km against the current of the stream in 1 hour and goes 1 km along the current in 10 minute...
Rating : 5
