Question

An alloy of zinc and copper weigh $12\frac{1}{2}kg$. If, in the alloy, the ratio of zinc and copper is $1:4$, find the weight of copper in it.

Answer 1

Weight of an alloy of zinc and copper $=12\frac{1}{2}kg$

The ratio of zinc and copper in the alloy $=1:4$

The weight of copper in alloy $=\frac{4}{5}of12\frac{1}{2}kg$

$=\frac{4}{5}\times \frac{25}{2}$

$=10kg$ (Ans)