On the final exam that I just took, the last problem went like this: A spotlight is shining on a building. It is 36 feet away from the building. A man that is 6 feet tall is walking toward the building. Calculate the rate of change in the length of his shadow if he is walking toward the building at a rate of -5 and he is currently 12 feet away from the building. I ended up with 100/3. Anywhere close? Thanks.