A street light is at the top of a 10 ft tall pole. A woman 6 ft tall walks away from the pole with a speed of 4 ft/sec along a straight path. How fast is the tip of her shadow moving when she is 50 ft from the base of the pole?

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- Nov 12th 2009, 10:03 PMbiermann33Word Problem
A street light is at the top of a 10 ft tall pole. A woman 6 ft tall walks away from the pole with a speed of 4 ft/sec along a straight path. How fast is the tip of her shadow moving when she is 50 ft from the base of the pole?

- Nov 13th 2009, 06:16 AMCalculus26
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- Nov 14th 2009, 05:01 AMCalculus26Correction
In the previuos post dy/dt is the rate at which the length of the shadaow is increasing.

for the tip of the shadow : Let s be the cooedinate of the tip of the shadow.

s= x + y

dst/dt = dx/dt +dy/dt = 4 + 6 =10