Question
A boat moves in a river where the ratio of the speed of
the stream to the downstream speed of the boat is 1:6. If it takes the boat a total of 20 hours to travel 144 km downstream and return 144 km upstream, how much time will it take to cover 180 km in still water?Solution
ATQ,
Let the downstream speed of a boat and the speed of stream be 6x km/hr and 'x' km/hr respectively.
Or, upstream speed of boat = 6x - x - x = 4x km/hr
ATQ,
(144/6x) + (144/4x) = 20
Or, (24/x) + (36/x) = 20
Or, (60/x) = 20
So, 'x' = 3
So, speed of boat in still water = 6x - x = 5x = 5 × 3 = 15 km/hr
So, required time = (180/15) = 12 hours
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All C are Z.
Conclusions:
I. Some A can be B.
II. Some C can...
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b. Some rats are lions
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II. Some lions are not dogs
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No Book is Pencil.
Some Pencil are Eraser.
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I. Some Eraser can be Pen.<...
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All pencils are glasses.
No glass is a jug.
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Some Cable are Table
No Table are Chair
All Chair are Rack
Conclusions:
I) Â Some Cable are not Rack...
Read the given statements and conclusions carefully. Assuming that the information given in the statements is true, even if it appears to be at variance...
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Some Circle are Square.
Only Square are Rectangle .
No Circle is a Cubo...
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Some TVs are laptops.
Some laptops are computers.
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I. Some time is second
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