Hacker News Reader

I think that's the point of the question: to see how you approach it. The 'correct' approach that they'd be looking for is 'Fermi estimation': https://en.wikipedia.org/wiki/Fermi_problem

View on HN

No, the point is to try to rationalize cargo-culting. Fermi did this, and Fermi was brilliant, so if we require candidates to do this we'll end up hiring people who are as brilliant as Fermi!

Here's a brainteaser: spot all the flaws in that chain of "reasoning".

Um, no. It's not cargo-culting. It's the correct way of estimating things. It has nothing to do with Fermi having done it. Some things actually have correct answers. 2 + 2 = 4, is not cargo culting.

You just moved the goalposts from looking for "a Fermi estimate" to looking for a correct answer.

Um...no. The goalposts have always been that the purpose of the brainteasers was to demonstrate reasoning skills. Using Fermi estimation is demonstrating reasoning skills. It's not like some trick that you have to know, it's not a formula. It's something any intelligent person would do on their own when faced with a task of this sort.

Reply on news.ycombinator.com