Paper money distribution

The four friends received money for collecting paper as follows: Miro received a quarter of the entire amount, Rob received a third of the remaining money, and Boris received half of the second remaining money. Peter had 1.50 euros left. How many crowns did Miro and Rob get together?

Final Answer:

s =  3 Eur

Step-by-step explanation:

$$\begin{gathered} m=x/4 \\ r=(x-m)/3 \\ b=(x-m-r)/2 \\ x=m+r+b+1.5 \\ x=x/4+(x-m)/3+(x-m-r)/2+1.5 \\ x=x/4+(x-x/4)/3+(x-x/4-r)/2+1.5 \\ x=x/4+x/4+(x-x/4-x/4)/2+1.5 \\ x=6 \\ m=x/4=6/4=\frac{3}{2}=1.5\text{eur} \\ r=(x-m)/3=(6-1.5)/3=\frac{3}{2}=1.5\text{eur} \\ b=(x-m-r)/2=(6-1.5-1.5)/2=\frac{3}{2}=1.5\text{eur} \\ s=m+r=1.5+1.5=3\text{Eur} \end{gathered}$$

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