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November 21, 2014

November 21, 2014

Posted by **Kara** on Monday, June 7, 2010 at 8:48pm.

- physics -
**drwls**, Monday, June 7, 2010 at 10:23pmLet V = stream velocity and v = boat velocity with respect to water. Both are in km/hr.

3 hr = 30/(V + v)

5 = 30/(V -v)

Solve those two equations in two unknowns for V and v.

5(V -v) = 3(V +v)

2V = 8v

v = V/4

3 = 30/(5V/4)= 120/5V

15V = 120

etc

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