Justify

50 bottles of red wine are to be purchased for a company party. In the first store, a bottle of wine costs €6.90, and they have a promotion where every fifth bottle is free when you buy four. In the second store, the same bottle costs €8.50, but there is a 28% discount on wines. Calculate where it is cheaper to buy the wine and justify your answer.

Final Answer:

x = A

Step-by-step explanation:

$$\begin{gathered} n=50 \\ r=100\%-28\%=1-\frac{28}{100}=0.72 \\ a=6.90\cdot (n-n/5)=6.90\cdot (50-50/5)=276\text{eur} \\ b=8.50\cdot n\cdot r=8.50\cdot 50\cdot 0.72=306\text{eur} \\ a<b \\ 276eur<306eur \\ x=A \end{gathered}$$

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