Answer: The price of peanuts realitve to that of raisins must be 2.
Explanation: Mathematically, relative prices are defined as:
Relative price of Good A with respect to Good B = Price of A / Price of B
So: Relative price of peanuts respect to raisins = Price of peanuts / Price of raisins
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Relative price of peanuts respect to raisins = 4 / 2 = 2.