Ahmed, Bianca, and Christopher, work full-time in the same shop in London. They work the same number of hours, serving the same number of customers, with the same job description. Their friend Davina also works full-time, with a similar job description, for the shop next door.
Ahmed earns three-quarters of Bianca’s wage, and two-thirds of Christopher’s. He earns £10,304 less than Davina every year. Why?