Floating Down a River - How Would You Solve It?

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cbenk121
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Topic: Floating Down a River - How Would You Solve It?

Sun Nov 15, 2009 8:35 pm

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OA is (A)

palvarez
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Mon Nov 16, 2009 11:18 am

(v-3)t = (v+3)(t-0.5) = 90 (v+3)/(v-3) = t/(t-.5) 2v/6 = 2(2t-.5) = 4t - 1 v = 12t-3 (12t-6)t = 90 (2t-1)t = 15 = 5.3 t = 3 (upsteam) downstream = 2.5

cbenk121
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Mon Nov 16, 2009 1:45 pm

palvarez wrote: (v-3)t = (v+3)(t-0.5) = 90 (v+3)/(v-3) = t/(t-.5) 2v/6 = 2(2t-.5) = 4t - 1 v = 12t-3 (12t-6)t = 90 (2t-1)t = 15 = 5.3 t = 3 (upsteam) downstream = 2.5 How'd you move from "(v+3)/(v-3) = t/(t-.5)" to "2v/6 = 2(2t-.5)"?

palvarez
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Mon Nov 16, 2009 1:49 pm

a/b = c/d (a+b)/(a-b) = (c+d)/(c-d) a/b = c/d add 1 both sides (a+b)/b = (c+d)/d subtract 1 both sides (a-b)/b = (c-d)/d Divide both (a+b)/(a-b) = (c+d)/(c-d)