Coins

The money - -coins are minted from the hardest bronze, which contains copper and tin in a ratio of 41:9. How much copper and tin are in 2kg of bronze money?

Correct answer:

m =  1.64 kg
c =  0.36 kg

Step-by-step explanation:

$$\begin{gathered} m=41/9\cdot c \\ m+c=2 \\ 41c-9m=0 \\ c+m=2 \\ Row2-\frac{1}{41}\cdot Row1\to Row2 \\ 41c-9m=0 \\ 1.22m=2 \\ m=\frac{2}{1.2195122}=1.64 \\ c=\frac{0+9m}{41}=\frac{0+9\cdot 1.64}{41}=0.36 \\ c=\frac{9}{25}=0.36 \\ m=\frac{41}{25}=1.64=\frac{41}{25}\text{kg}=1.64\text{kg} \end{gathered}$$

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