Question

An alloy is made from 30% copper, 35% zinc, and the rest is nickel. Find the weight of nickel in 740 gm of the alloy.

Answer 1

$$\begin{gathered} \mathrm{Percentage}\mathrm{of}\mathrm{copper}\mathrm{in}\mathrm{alloy}=30\% \\ \mathrm{Percentage}\mathrm{of}\mathrm{zinc}\mathrm{in}\mathrm{alloy}=35\% \\ \mathrm{Percentage}\mathrm{of}\mathrm{nickel}=\left[100-\left(30+35\right)\right]\%=35\% \\ \mathrm{Let}\mathrm{weight}\mathrm{of}\mathrm{nickel}\mathrm{is}\mathrm{x}\mathrm{gm}\mathrm{in}\mathrm{the}\mathrm{alloy} \\ \mathrm{Now},35\%\mathrm{of}740=\mathrm{x} \\ \Rightarrow \frac{35}{100}\times 740=\mathrm{x} \\ \Rightarrow \mathrm{x}=259 \\ \mathrm{So},\mathrm{weight}\mathrm{of}\mathrm{Nickel}\mathrm{in}\mathrm{the}\mathrm{alloy}=259\mathrm{g} \end{gathered}$$