#Solve for x

18 messages · Page 1 of 1 (latest)

uncut shoal
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If I want to solve for x here, what should I do?
(K/y)=24
(K/x+y)+(K/x-y)=10
(K/1.4x+y)+(K/1.4x-y)=7

Required = (K/x+y)

If it helps, K is a constant and used to denote distance between points A and B of a river between which a river is flowing in the direction of B
K/y=24 means a free floating object takes 24h from A to reach B
x denotes speed of boat, and y denotes speed of stream, x+y denotes downstream speed and x-y denotes downstream speed.
1.4x+y and 1.4x-y denotes an increase in the boat's speed by 40%
So a boat takes 10hr to travel both upstream and downstream, and the boat when its own speed is increased by 40% will take 7hr to travel both upstream and downstream

cloud craneBOT
hushed mulch
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You can get k/x+y or k/x-y but I think you can't solve for x

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Also a=5 since a=x/y and x,y are both positive

uncut shoal
# hushed mulch

Hence the time taken upstream is 4hrs and downstream is 6hrs.

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Then the time taken for still water should be the HM of 4 and 6 (since speeds are always in an Arithmetic Progression eg. Boat+Stream, Boat, Boat-Stream)

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That makes the answer 4.8hrs for x?

hushed mulch
hushed mulch
hushed mulch
uncut shoal
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(K/y)=24
(K/(x+y))+(K/(x-y))=10
(K/(1.4x+y))+(K/(1.4x-y))=7

Required = x

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So, this way I guess it would give the same result.

uncut shoal
hushed mulch
uncut shoal
hushed mulch
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Sure. Glad I could help!

uncut shoal
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