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Old 04-25-2013   #3
imad 150

 
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Quote:
Originally Posted by mas1 View Post
a) f'(vs) = 600((772.4 - 45)/(772.4 - vs))

b) 620 = 600((772.4 - 45)/(772.4 - vs))
(620/600) = (727.4/(772.4 - vs))
1.0333 = 727.4/(772.4 - vs)
31/30 = 727.4/(772.4 - vs)
cross multiplying gives:
(30)(727.4) = (31)(772.4 - vs)
21822 = 23944.4 - 31vs
31vs = 2122.4
vs = 68.465 mph
ooohhhhh
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