Question

In some quantity of ghee, $60\%$ is pure ghee and $40\%$ is vanaspati. If $10kg$ of pure ghee is added, then the strength of vanaspati ghee becomes $20\%$. The original quantity was

• A. $10kg$
• B. $15kg$
• C. $20kg$
• D. $25kg$

Answer 1

Answer: (A)

$10kg$

Let initial quantity of ghee be $100x$
it contain 60x pure ghee and 40x vanaspati
after adding 10 kg pure ghee
$totalweight=(100x+10)kg$
it contains $(60x+10)$ kg pure ghee and 40x vanaspati
% of vanaspati $=\frac{40x}{(100x+10)}=20/100$
% of vanaspati $=\frac{40x}{\left(100x + 10\right)}= 1/55 \times 40x = \left(100x + 10\right) 200x = 100x + 10100x = 10$ which is initial weight of ghee.