google microsoft interview n.
Download
Skip this Video
Loading SlideShow in 5 Seconds..
Google/Microsoft interview PowerPoint Presentation
Download Presentation
Google/Microsoft interview

Loading in 2 Seconds...

play fullscreen
1 / 8

Google/Microsoft interview - PowerPoint PPT Presentation


  • 86 Views
  • Uploaded on

Google/Microsoft interview. Problem 1. Estimate the weight of a 747. . Problem 1. Estimate the weight of a 747. Ok, 747 is a vehicle designed to carry people. We don’t know much about planes, but let’s think by proxy. What other large vehicles carry passengers?

loader
I am the owner, or an agent authorized to act on behalf of the owner, of the copyrighted work described.
capcha
Download Presentation

PowerPoint Slideshow about 'Google/Microsoft interview' - merle


An Image/Link below is provided (as is) to download presentation

Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author.While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server.


- - - - - - - - - - - - - - - - - - - - - - - - - - E N D - - - - - - - - - - - - - - - - - - - - - - - - - -
Presentation Transcript
problem 1
Problem 1
  • Estimate the weight of a 747.
problem 11
Problem 1
  • Estimate the weight of a 747.
  • Ok, 747 is a vehicle designed to carry people. We don’t know much about planes, but let’s think by proxy. What other large vehicles carry passengers?
  • Busses. Assume 747 = 6 buses. 4 in a row + 2 on top. Each bus ~ 60 people. So 747 ~ 360 people. Sounds about right. A bus weighs 5-10 tons. So, a 747 weighs between 6*5 and 6*10 = 30-60 tons. (43 tons, actually).
problem 2
Problem 2
  • In a country where couples want boys, they use the following strategy: couples have children until they have a boy, then stop. What is the ratio of boys to girls in this country?
problem 21
Problem 2
  • In a country where couples want boys, they use the following strategy: couples have children until they have a boy, then stop. What is the ratio of boys to girls in this country?
  • 1St step: get your feet wet. Play with the problem. Start with N=2 couples. You can have 2 boys. Or you can have 4 girls and then 2 boys. So, looks like all possible ratios are possible.
problem 22
Problem 2
  • In a country where couples want boys, they use the following strategy: couples have children until they have a boy, then stop. What is the ratio of boys to girls in this country?
  • 1St step: get your feet wet. Play with the problem. Start with N=2 couples. You can have 2 boys. Or you can have 4 girls and then 2 boys. So, looks like all possible ratios are possible.
  • Of course, each of these outcomes has its own different probability. So, we could consider all outcomes and work out the probabilities. But that would be kind of difficult…
problem 23
Problem 2
  • In a country where couples want boys, they use the following strategy: couples have children until they have a boy, then stop. What is the ratio of boys to girls in this country?
  • Alternative. Let’s go to the large N limit. Appropriate for “country”. Will simplify things. Exactly ½ couples will have boys, ½ will have girls.
  • First, what is easier to find, NB or NG? Of course, NB = N. So, need to focus on NG
  • Draw a BIG diagram.
problem 24
Problem 2

Count girls: NG = N/2 + N/4 + N/8 + … = N = NB

Offspring generation #

3

N/8

BBB GGG

2

BBBBBB GGGGGG

N/4

BBBBBBBBBBBBB GGGGGGGGGGGGG

N/2

1

N/2

couples