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Hadar's Product Interviewing Toolkit
Hadar's Product Interviewing Toolkit
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Estimation

Break down the problem. Round numbers to make calculating easier. The final answer doesn't matter, it's how you got there.
Note: This is not commonly asked in PM interview loops. Google does and some startups may.

What they're looking for

Are you able to break down a big complex problem into smaller pieces?
Are you comfortable making educating guesses?
These questions are often referred to as
Fermi problems
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Types of questions you may be asked here

How much does an airplane weigh?
How many productive hours per year are lost due to traffic congestion?
How many bicycles are there in America?
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How to approach these

Clarify the problem
eg: Is the airplane full of people? Traffic internationally or in America? Does “bicycles” include motorcycles?
Scope the problem to something easier to think about
eg: The weight of a plane could be broken down into the wings, engine, all the seats, etc.
Estimate the subcomponents and then combine it all
Talk through possible errors in your estimation
eg: Depends on the material the plane is made of; people might be making productive use of their time in traffic nowadays; transition to bikesharing services may have reduced individual bike ownership, etc.

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👉 Next up:
After the interview
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