Dollar just doesn't make any cents...

Penny drops on coinage hassle

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CASH can't be king stateside as it's impossible to tell the difference between it all.

The green bills featuring former presidents and founding fathers are all notes of the same size and colour. It was apparently a cost-saving measure way back when that never changed as counterfeit technology advanced.

It's the most widely used currency in international transactions and the currency for 11 other countries beyond the US borders.

But it's far more difficult to use than colour-coded and different size denominations in euro given you can't tell them apart in your wallet.