Decoration collection discount

The collection of Christmas tree decorations costs € 12 before Christmas. After Christmas, we could buy it for three-fifths of the original amount. By how many euros did the collection become cheaper?

Final Answer:

x =  4.8 Eur

Step-by-step explanation:

$$\begin{gathered} a=12\text{Eur} \\ b=\frac{3}{5}\cdot a=\frac{3}{5}\cdot 12=\frac{3\cdot 12}{5}=\frac{36}{5}=7.2\text{Eur} \\ x=a-b=12-\frac{36}{5}=\frac{12\cdot 5}{5}-\frac{36}{5}=\frac{60}{5}-\frac{36}{5}=\frac{60-36}{5}=\frac{24}{5}=\frac{24}{5}\text{Eur}=4.8\text{Eur} \end{gathered}$$

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