Proving that age is just a number, Berkshire Hathaway chief executive, Warren Buffett, 88, and vice-chairman, Charlie Munger, 95, answered questions for seven hours at the company’s AGM this weekend.

Berkshire Hathaway, the conglomerate run by billionaire Warren Buffett, has reported a quarterly operating profit rise of 67%, as insurance underwriting rebounded and several business units benefited from a growing economy.