Meet the world's youngest billionaire

Have you ever wondered who the world's youngest billionaire is?

You'll never believe how old (or young) she is.

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Alexandra Andresen is the world's youngest billionaire and she has a net worth of $1.2 billion.

How, you might ask?

She inherited a stake in her family's investment company Ferd Holding.

The Norwegian heiress has chosen to stay away from the family business, so how does she spend her time?

She's an award-winning horse racer and is currently training for the 2020 Olympic Games in Tokyo.

Her sister, Katharina, is the second youngest billionaire - at 21, she's also worth $1.2 billion.