Question

The ratio of weights of zinc and copper in an alloy is 5:8. If the weight of copper in a sample of this alloy is 12 g, what is the weight of zinc?
(2 Marks)

Answer 1

Given : Ratio of weights of zinc and copper = 5 : 8

Let the weight of zinc for 12 g of copper be 'x'.

$\frac{Zinc}{Copper}$ = $\frac{5}{8}$ = $\frac{x}{12}$
(1 mark)
<!--td {border: 1px solid #ccc;}br {mso-data-placement:same-cell;}--> ⇒ x = $\frac{5\times 12}{8}$

⇒ x = 7.5 g

$\therefore$ The weight of zinc is 7.5 g.
(1 Mark)