Question

If $2$ kg of metal of which $\frac{1}{3}$ is zinc and rest copper be mixed with $3$ kg of metal of which $\frac{1}{4}$ is zinc and rest copper, what is the ratio of zinc to copper in the mixture?

• A. $13:35$
• B. $12:30$
• C. $15:40$
• D. $17:43$

Answer 1

Answer: (D)

$17:43$

1st metal :
Quantity of zinc $=\frac{1}{3}\times 2kg=\frac{2}{3}kg$
$\therefore Quantityofcopper=[2-\frac{2}{3}]kg=\frac{4}{3}kg$

2nd metal :
Quantity of zinc $=\frac{1}{4}\times 3kg=\frac{3}{4}kg$
$\therefore Quantityofcopper=[3-\frac{3}{4}]kg=\frac{9}{4}kg$

In the mixture, the required ratio
$[\frac{2}{3}+\frac{3}{4}]:[\frac{4}{3}+\frac{9}{4}]=\frac{17}{12}:\frac{43}{12}=17:43$