Kilograms 83204

Nine kilograms of bell metal contain 7 kg of copper, the rest of which is tin. How much copper and how much tin were used to cast five bells? Each of the two larger bells weighed 535kg, and each of the remaining three smaller ones weighed 286kg.

Correct answer:

c =  1499.5556 kg
s =  428.4444 kg

Step-by-step explanation:

$$\begin{gathered} m=2\cdot 535+3\cdot 286=1928\text{kg} \\ c:s=7:(9-7)=7:2 \\ c=\frac{7}{9}\cdot m=\frac{7}{9}\cdot 1928=\frac{7\cdot 1928}{9}=\frac{13496}{9}=\frac{13496}{9}\text{kg}=1499.5556\text{kg} \end{gathered}$$

$s=m-c=1928-\frac{13496}{9}=\frac{1928\cdot 9}{9}-\frac{13496}{9}=\frac{17352}{9}-\frac{13496}{9}=\frac{17352-13496}{9}=\frac{3856}{9}=\frac{3856}{9}\text{kg}=428.4444\text{kg}$

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