Boating Trip

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Source: — Problem Solving |

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by sudhir3127 » Sat Aug 09, 2008 9:49 pm
Speed = distance/time

use this and set up the 2 equations

For going up the river :
90 = t * (v - 3)

For going down the river :
90 = (t - 0.5) * (v + 3)

solve for the equations.to get 2.5

hence 2.5 for downstream and 3 hrs for upstream..

hope it helps..

PS: be careful while solving the equation...

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by raunekk » Sat Aug 09, 2008 9:55 pm
D=RT

Time taken upstream = 90/v-3...(1)

time taken downstream= 90 / v+3..(2)

upstream takes 0.5 hour more..

thus..( 90/v-3) - (90/v+3) = 0.5

solving we get v = 33

substitute in (2)...

time taken = 90/36= 2.5

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by ajmoney09 » Sat Aug 09, 2008 10:27 pm
thanks raunekk and sudhir you guys be very helpful todaay! Major props and thanks again!!!

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by kshin78 » Sat Aug 09, 2008 10:34 pm
Can any of you please provide how you solved the equation? It's taking me forever to solve for either v or t. any suggestions?

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by kshin78 » Sun Aug 10, 2008 12:46 pm
kshin78 wrote:Can any of you please provide how you solved the equation? It's taking me forever to solve for either v or t. any suggestions?
never mind - figured it out. that was a longggggg process though...don't know if i can do that in two minutes..more like 4-5 minutes!

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by smclean23 » Sun Aug 10, 2008 4:59 pm
How did you guys end up solving the equations?

Its taking me extremely long.....

THANKS!