When the world's richest man and his wife decided to divorce, the numbers were always going to be big. And so it proved this week, when Amazon founder Jeff Bezos and his wife MacKenzie agreed the terms of their split. MacKenzie Bezos will keep a 4% stake in the online retail giant. Her stake is worth $35.6bn (£27bn) on its own, making her the world's third-richest woman (and the 24th richest person in the world). The French heiress to the L'Oréal cosmetics fortune who, along with her family, owns 33% of the company.