2.derek is the 11th tallest person in the room and the 9th shortest. how many people are in the room?

There are 11 people in the room. It's almost like a trick question, out of the 11 tall people he is among the 9 shortest (Tall) people, so from the Third Tallest person to the Eleventh Tallest person they are considered the 9 Shortest (Tall) People. It's kind of hard to explain trick questions like that. The reason why i know that is because, In high school mathematics they try to trick you to see if you will get fooled or not. Its like saying you order a Large Pizza and the guy asks you how many slices do you want it cut into? No matter how many slices you cut the pizza up to, your still gonna eat the same amount of pizza. 

If he is the 11th tallest and the 9th shortest then there are 20 people in the room

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