I really don't understand all the vitriol around these types of questions. Yes, rough estimation, sense of magnitude, and ability to apply basic math to solve p

I really don't understand all the vitriol around these types of questions. Yes, rough estimation, sense of magnitude, and ability to apply basic math to solve problems are important real life skills, and very much prerequisites in an engineering discipline. If I asked you to estimate roughly how many thumbnail images would fit in the main memory of your smartphone, would that be a better question? You should also, as an engineer, understand that the ping-pong ball question is merely a different instantiation of the exact same base abstraction. If you can answer the question easily, humor the interviewer and move on -- because lots of people can't. I actually find it kind of fun, because then you get to see how close you get. Also, as you become promoted, being able to work autonomously with minimal supervision and incomplete information is indeed part of your job description. If I were hiring someone, I'd want someone with a solid growth trajectory.