Even converting to pure metric won't save you. Comparing something at 425 grammes versus 475 grammes is a nightmare. As jseal said, unit pricing.

What pisses me off is that fuel companies have imposed a cycle on the fuel price, so that fuel is dearer when you are most likely to buy (Friday, Saturday and Sunday) and less on days you're less likely to buy. It's a rip-off that the fuel companies have pussy-whipped the government watchdogs into accepting.

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