Cu thief

The thief stole 25 meters of copper wire with a cross-section area of $s mm². Calculate how much money is earned on scrap redemption if copper is redeemed for 5.1 Eur/kg. Copper's density is 8.96 t/m³.

Correct answer:

x =  117.7 Eur

Step-by-step explanation:

$$\begin{gathered} L=25\text{m}\to \text{cm}=25\cdot 100\text{cm}=2500\text{cm} \\ S=103/10^2=\frac{103}{100}=1.03{\text{cm}}^2 \\ \rho =8.96{\text{t/m}}^3\to {\text{kg/m}}^3=8.96\cdot 1000{\text{kg/m}}^3=8960{\text{kg/m}}^3 \\ p=5.1\text{eur/kg} \\ V=S\cdot L=1.03\cdot 2500=2575{\text{cm}}^3 \\ {V}_1=V\to {\text{m}}^3=V:1000000{\text{m}}^3=2575:1000000{\text{m}}^3=0.00258{\text{m}}^3 \\ m=\rho \cdot V_1=8960\cdot 0.0026=\frac{2884}{125}=23.072\text{kg} \\ x=p\cdot m=5.1\cdot 23.072=117.7\text{Eur} \end{gathered}$$

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