Google PM Interview Question: How Many Hours Are Wasted at an Airport?

A real guesstimate question from a Google PM interview: how many hours get wasted at an airport every day? Most candidates fail this by getting the granularity wrong, either drowning in variables or blurting out a number they can't back up. Watch the full build on a live Google Sheet: a formula broken into three named levers, a passenger population built up from gates and flight turnover instead of guessed, real assumptions defended live, an actual number, and the model cross-checked with a second method built entirely on the spot, no memorized statistics, before the interviewer has to ask. Timestamps: 0:00 | Why guesstimates get graded differently 0:50 | Who this channel is for 1:05 | What this question is actually testing 1:50 | The two ways this answer fails 2:45 | How I'd answer this 3:19 | Clarify 4:20 | Layout Approach 5:20 | Breakdown the formula 5:55 | Build the population 7:20 | Estimate time wasted 9:54 | Calculate the number 10:22 | Sanity check 13:15 | Where the real signal landed 14:00 | The real bar on a guesstimate 14:25 | Your turn Comment with a guesstimate question you've been asked, and I'll break it down. You can mail me at muthu.rajendran85@gmail.com for 1:1 coaching. Tags: PM interview India, guesstimate interview question, estimation question PM interview India, Google PM interview, Senior PM interview tips, Director PM interview, product sense interview India, PM interview tips 2026