Interview Question for Financial Analyst at Fidelity Investments:

Yes, it is a think out loud and reasoning test. Make it personal "I don't ever dial 411 because I'm cheap, but I know some do. My grandmother and my child couldn't do it, so if you eliminate all those types of people, you might be left with 200 million phone users in the US. If I am at work, I would Google first, so that has changed how people use phones. I suppose the 200 million people probably average 1 call per year, so 200 million calls."

So, without making a crazy answer like 10 time a day per person, it is a little hard to challenge.