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A boat running upstream takes 8 hours 48 minutes to cover a certain distance, while it takes 4 hours to cover the same distance running downstream. What is the ratio between the speed of the boat and speed of the water current respectively?
2 : 1
3 : 2
8 : 3
Cannot be determined
None of these
Read Solution (Total 5)
-
- u-v=x/8.8.....(1)
u+v=x/4.......(22)
calculating both equation,
u=2x/11
v=3x/44
u/v=8/3 - 10 years agoHelpfull: Yes(12) No(4)
- Then, distance covered upstream in 8 hrs 48 min = Distance covered downstream in 4 hrs.
8 hrs and 48 minutes = 528 minutes
4 hrs = 240 minutes
then, 528/240 = 11/5 minutes
we know that speed are different in down stream and upstream.
if both are in opposite direction then 11+5/2 =8
------------------- same direction then 11-5/2 =3 ( here 2 is to take average )
therefore ratio is 8:3
- 9 years agoHelpfull: Yes(8) No(2)
- Nine of these
If B is speed of boat
and
s is speed of stream and x is distance travelled
B-S = x/(8+(48/60))
B+S = x/4
solving these, we get
B/S = 181/171
so none of these - 13 years agoHelpfull: Yes(2) No(25)
- Speed=distance/time
therefore distance=speed*time.
let consider speed at upstream is "x" and at downstream is "y", then distance covered (upstream in 8 hrs 48 min)= x*8*4/5
here 8hours and 48minutes=8*48/60=8*4/5
and distance covererd (downstream in 4hours=y*4
to relate both these equation
from question ,we know that distance covered are same
therefore x*8*4/5 = y*4
y=11/(5*x)
we know that speed are different in down stream and upstream.
if both are in same direction
take difference(x-y)
if they are in opposite
take sum(x+y)
Required ratio =(x+y)/2 : (x-y)/2 // here 2 is to take average.
then answer is 8:3 - 9 years agoHelpfull: Yes(2) No(3)
- from R.S agarwal we can get the answer 8:3
- 7 years agoHelpfull: Yes(2) No(1)
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