Ask a question like: How many people in Japan do you think are married?
There's no right or wrong answer really, you're just trying to get at how they come up with a number.
A hypothetical answer: Let's see, let's say Japan has 50 million people, of those 50 Million maybe 35 Million are consenting adults. Japan is a pretty traditional culture so probably a large percentage of...
You get the idea.
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