AQR 1-1 to 1-5 Review

  1. Name the true facts about Fermi questions.

Fermi questions were named after an Italian physicist.

Fermi questions rely on making logical assumptions about a situation to reach an estimate.

Fermi questions have limited information, but are possible by using mathematics to find a reasonable Numerical estimate

A classic Fermi question is “How many piano tuners are there in the city of Chicago?”

  1. What is an aspect ratio?

The ratio w:h in an image on a screen is an aspect ratio.

  1. What is the fundamental counting principle?

When there aremways to do one thing,andnways to do another,then there arem×nways of doingboth.

  1. What mathematical operation is used in the Fundamental Counting Principle? Multiplication
  1. What is the height of a screen of an 80 inch HD television with an aspect ratio of 16:9?39.21
  1. What is the width of a screen of an 80 inch HD television with an aspect ratio of 16:9? 69.72
  1. What is the area of a screen of an 80 inch HD television with an aspect ratio of 16:9? 2734inches squared
  1. When changing the size of a rectangular image using a computer-drawing program, how is it possible to maintain the same aspect ratio? Increase the diagonal so that the width and height (length) are increased at the same rate.
  1. One rule of thumb when estimating crowds is that each person occupies 2.5 square feet. Use this rule to estimate the size of a crowd watching a parade along a 3.5 mile section that is 5 feet deep standing on both sides of the street. 73,920
  1. If 15 people fit in a 5 foot by 5 foot square then estimate the size of a crowd watching a parade along a 3. mile section that is 5 feet deep standing on both sides of the street. 95040
  1. How many gallons of water would be need to completely fill a swimming pool with dimensions 10 ft by 12 ft by 5ft? (Consider that 7.48 gallons is in a cubic foot) 4488
  1. How many minutes will it take to fill up at a rate of 3 seconds per liter. 850.48 minutes
  1. Canada uses a zip code that consists of a letter, a digit, a letter, a digit a letter and a digit, ei: L # L # L #. Postal codes do not include the letters D, F, I, O, Q or U, and the first position also does not make use of the letters W or Z. How many different postal codes are used? 7,200,000 (18x10x20x10x20x10)
  1. Who was Enrico Fermi?He was an Italian physicist known for his participation in the Los Alamos atomic bomb project (code named the “Manhattan Project”) during World War II. Fermi is best known for his contributions to nuclear physics and the development of quantum theory.
  1. How many license plates can be produced when the plate has # # # L L # the letters cannot be a vowel and the first digit cannot be 0? 3,969,000