4.A
boat takes 19 hours for travelling downstream from point A to point B and
coming back to point C midway between A and B. If the velocity of the stream is
4 kmph and the speed of the boat in still water is 14 kmph, what is the
distance between A and B?
[A]
160 km
[C]
200 km
[B]
180 km
[D]
220 km
Answer : [B]
Explanation :
|
Speed
downstream = (14 + 4) km/hr = 18 km/hr;
|
|
Speed
upstream = (14 - 4) km/hr = 10 km/hr
|
|
Let
the distance between A and B X km, Then,
|
|
|
|
+
|
|
=
19
|
|
|
|
+
|
|
=
19
|
|
|
|
=
19
|
|
|
|
x = 180 km.
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|
