# Science:Math Exam Resources/Courses/MATH104/December 2012/Question 05 (b)

MATH104 December 2012
Other MATH104 Exams

### Question 05 (b)

Alice is 5 ft tall and Bob is 6 ft tall. At some instant they are both walking towards a street lamp 15 ft high with Alice west of the lamp and Bob east of the lamp. Suppose at this instant, Alice is walking at 4 ft/s and the distance between the tips of their shadows is decreasing at 11 ft/s.

How fast is Bob walking?

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