Google Quantitative Analyst interview questions

The on-site interviews were not so easy. One thing to note: I have 20 years of experience and a strong track record of getting results. The interviewers had zero interest in what I've done before. Instead it was white boarding all the way. Felt more like an old-school math class -- go to the board and solve this problem -- than a job interview. Toughest question? Honestly, this was 4 years ago and I don't recall precisely. I think it was how to determine mean standard deviation of two blended datasets for which you know their means and standard deviations (and maybe Ns) but for which you've lost the original data. Turns out it's a classic you'll probably encounter in first year statistics, but I hadn't thought about it in about 25 years and so stumbled.