Phoebe Gates asks everyone she interviews this unexpected question

Phoebe Gates, the youngest daughter of billionaire Microsoft founder Bill Gates and philanthropist Melinda French Gates, has a low-key terrifying question she throws at those interviewing for a role at her startup. 

The 23-year-old recently raised a $35 million Series A for Phia, the AI shopping agent she cofounded in April 2025 with her Stanford University roommate Sophia Kianni. The startup, which has since garnered more than 1 million users and grown revenue elevenfold, is currently valued at around $185 million. 

Gates recently joined Brian Sozzi, Yahoo Finance executive editor, on the Opening Bid Unfiltered podcast and revealed her go-to interview question for prospective candidates.

“I stole this from another founder,” she said. “‘How much do you think California state spends on healthcare? And do a bottoms-up approach for how you would build that out.’”

She told Sozzi, “I’ll ask that for every single role. I’ll ask that for sales, I’ll ask that for marketing, I’ll ask that for engineering.” 

It’s not because she expects candidates to know the answer off the top of their head. Instead, she said it highlights “how someone goes through a logical approach to solving that question.”

Curveball interview questions, designed to surprise candidates and test problem-solving ability or performance under pressure, are famously beloved by founders. Microsoft apparently posed the question “Why are manhole covers round?” to interviewees. 

Elon Musk asked, “You’re standing on the surface of the Earth. You walk 1 mile south, 1 mile west, and 1 mile north. You end up exactly where you started. Where are you?”

Many will relate to the panicked feeling that arises upon being asked to sell a pen or divulge their greatest weakness. As entry-level roles become scarcer and the competition for top talent grows fiercer, hiring managers are increasingly getting creative to single out the cream of the crop. 

Still, researchers have questioned the usefulness of trick questions against other evidence-based assessments. 

As Phia continues to grow, it’s not the only question Gates has up her sleeve. When it comes to hiring salespeople, she asks candidates the craziest thing they’ve done to close a deal. “That teaches you a lot about how far they’ll go, how dedicated they are to do something,” she said. 

While Phia has accepted no money from Gates’s parents—“I have a chip on my shoulder,” she admitted on the podcast—she did share one of the most important lessons she’s learned from her parents about entrepreneurship. 

“From my dad, I’ve really learned that your team is the core of what you’re building,” she said. “You can’t do anything without an incredible team.”