Business schools boast that mixing with people from different countries forces their students to broaden their horizons and question their assumptions.

ECONOMIST: Schumpeter

Still, it makes the very idea of a president mixing with the people he is elected to serve seem like a well-intentioned but ultimately bittersweet illusion.

CNN: Barack Obama slept here

Others suggestions included treating friends and relatives to a firework display by mixing the ashes with gunpowder, while some people wanted a small amount of their remains placed in a specially designed locket for their loved ones to wear.

BBC: Living it up at the funeral

"It's always unfortunate when people in power start mixing politics with sports, " he said.

BBC: IPL cricket: India media attacks Sri Lanka player ban

"When I first opened my shop in the '80s, people were outraged by mixing antiques with modern pieces, " she explained.

WSJ: The Un-Vain Vanity Table

And more people are mixing their beer, half-and-half with lemonade, coke or even grapefruit juice.

FORBES: Beer? Germans Say Nein, Danke

The mixing of races so evident in Brazil will become more prevalent around the world, Professor Gates believes, with people originating from a sole geographical area becoming increasingly rare.

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