Trump, Kennedy double down on their impossible mathematics claims

Donald Trump and his Health Secretary Robert F Kennedy Jr have doubled down on their mathematically incorrect claims about how percentages work.

The US president has repeatedly claimed his policies would reduce prescription drug prices by as much as 600 per cent.

Such a claim is mathematically impossible.

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But speaking in the Oval Office, Kennedy explained how Trump's maths worked.

"(A Democratic senator claimed) it's mathematically impossible to have a drug drop by 600 per cent," he said.

"I said, 'Well, if the drug was $100 and it raises to $600, that would be a 600 per cent rise. If it drops from $600 to $100, that's a 600 per cent savings.'"

Trump added: "Right."

Both Trump and Kennedy are wrong. 100 per cent represents the whole of something. It is impossible to reduce anything beyond 100 per cent of itself.

The senator Kennedy was referencing was Elizabeth Warren, who grilled him at a committee hearing yesterday.

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She criticised Trump's bad maths on the topic of drug prices.

"Which I think means companies should be paying you to take their drugs," Warren said.

Kennedy defended Trump's maths at the hearing.

"President Trump has a different way of calculating," he said.

"There's two ways of calculating percentages."

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