Cu thief

The thief stole 142 meters copper wire with a cross-section area of $s mm². Calculate how much money gets in the scrap redemption if redeemed copper for 5.3 Eur/kg. The density of copper is 8.96 t/m³.

Correct answer:

x =  539.5 Eur

Step-by-step explanation:

$$\begin{gathered} L=142\text{m}\to \text{cm}=142\cdot 100\text{cm}=14200\text{cm} \\ S=80/10^2=\frac{4}{5}=0.8{\text{cm}}^2 \\ \rho =8.96\cdot 1000=8960{\text{kg/m}}^3 \\ p=5.3\text{eur/kg} \\ V=S\cdot L=0.8\cdot 14200=11360{\text{cm}}^3 \\ {V}_1=V\to {\text{m}}^3=V:1000000{\text{m}}^3=11360:1000000{\text{m}}^3=0.01136{\text{m}}^3 \\ m=\rho \cdot V_1=8960\cdot 0.0114=101.7856\text{kg} \\ x=p\cdot m=5.3\cdot 101.7856=539.5\text{Eur} \end{gathered}$$

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