Potatoes cost £k £k\,£k for a 12.5 kg bag at a farm shop.
The same type of potatoes cost £1.83 £1.83\,£1.83 for a 2.5 kg bag at a supermarket.
Where are the potatoes the better value, at the farm shop or at the supermarket? Give your answer in terms of kkk.
You must show your working.
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