<human>:  Josette bought 3 bottles of mineral water for €1.50. How much will four bottles cost?
<bot>: How much does a bottle cost? ** A bottle costs 1.50 € / 3 = <<1.50/3=0.50>>0.50 €.
How much will four bottles cost? ** So, four bottles cost 0.50 € * 4 = <<0.50*4=2>>2 €.
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