FERMI QUESTIONS (Sorry
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 How tall is this building?
 "No Lane Changes Next 600 Feet" How long until you can change
lanes?
 What is the linear velocity of the earth around the sun?
 How many trees are there in <pick your favorite
location>?
 How long would it take to walk from New York to Los Angeles?
 How many drops of water are in the Atlantic?
 How much human blood is there in the world?
 Estimate the number of gas stations in the US?
 How many protons are there in the sun?
 How many kilograms of water fall down Niagara Falls each year?
 How many feet of wool in a sweater?
 How many trees are there in <pick your favorite
location>?
 How long would it take to walk from New York to Los Angeles?
 How much air do you breath in a lifetime?
 How many McDonald's are there in the U.S.?
 What is the linear velocity of the earth around the sun?
 How many drops of water are in the Atlantic?
 How much human blood is there in the world?
This should give you a hint as to what a Fermi Question is like.
Your answer should include your reasoning and an answer that is a
power of 10 only. For example, there about 1875 students attending a
high school. If asked to do a Fermi estimation as to the number of
students in the school without knowing the actual number a reasonable
answer might be
 There are an estimated average of 23 students in every class.
 There are an estimated 105 full time teachers on staff.
 In a given school day of 6 periods, a teacher will not be
teaching 1 period a day.
 Therefore 5/6 of a the staff will be teaching all the
students. (5/6) of 105 is 88 classes.
 (88 classes)(23 students/class) is about 2000 students.
 reported answer is 2 X 10^3.
 Your estimated numbers don;t need to be this exact. Actually,
most numbers are so big that it is almost impossible to be exact.
