Question

In what proportion must water be added to spirit to gain 20% by selling it at the cost price?

• A. 1 : 5
• B. 2 : 5
• C. 3 : 5
• D. 4 : 5
• E. None of the above

Answer 1

The correct option is A 1 : 5

Let, the C.P. of the spirit =Rs 10 per litre.
S.P. of the mixture =Rs 10 per litre.
Profit =20%
$\therefore$ C.P. of the mixture $=Rs\frac{10\times 100}{120}$
=Rs $\frac{25}{3}$ per litre

$\frac{Quantityofwater}{Quantityofspirit}=\frac{\frac{5}{3}}{\frac{25}{3}}=\frac{1}{5}$
Ratio of water and spirit =1 : 5.