Many cars (quite a few of them in America) already run on a mixture of petrol and ethanol.

ECONOMIST: The future of energy

Diesel engines can run on any mixture of petroleum or biodiesel from B5 to B100(100% biodiesel), with no modifications.

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The hospital is run by a mixture of civilian and uniformed medical staff.

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Most Brazilian cars can run on a mixture of ethanol and petrol, thanks in part to the flex-fuel engine, developed in the country.

ECONOMIST: Schumpeter: The Brazilian model | The

As America struggles to extend health-care coverage while curbing health-care costs, we face a decision that is more important than whether we have a public-insurance option, more important than whether we will have a single-payer system in the long run or a mixture of public and private insurance, as we do now.

NEWYORKER: The Cost Conundrum

It will invest mainly in government gilts at the outset, moving to company shares in the middle of your life and moving back to a mixture of gilts and cash on the run-in to your expected retirement age.

BBC: Investment choices after pension auto-enrolment

There will be a mixture of afternoon and evening meetings with races run over jumps and on the flat.

BBC: Courses extend free entry offer for horse racing

In Brazil 80% of new vehicles run on ethanol, petrol or a mixture of both.

ECONOMIST: On Canada's border

But it turns out that pilots can run the engine better by adding some air and subtracting some gas in the fuel mixture.

FORBES: Institutional Stupidity, III