Question

A milkman buys milk at Rs. $25$ per litre and adds $\frac{1}{4}$ of water to it and sells the mixture at Rs. $25$ per litre. His gain (in %) is:

• A. $25$
• B. $20$
• C. $30$
• D. $15$

Answer 1

The correct option is A $25$

Cost price of one litre milk$=Rs.25$

After adding $1/4$ liter of water, we can say that

$CP$ of $(1+\frac{1}{4})l=\frac{5}{4}l=Rs.25$

$⟹$ cost of 1L milk$=Rs.\left(\frac{25\times 4}{5}\right)=Rs.20$

$SP=Rs.25$

gain$\%=\frac{25-20}{20}\times 100$

$⟹$gain$=25\%$