Question

By selling tea at Rs. $120$ per kg, a shopkeeper makes a profit of $20\%$. By how much should be increase his S.P., so as to gain $30\%$.

• A. $9\frac{1}{3}$%
• B. $8\frac{2}{3}$%
• C. $8\frac{1}{3}$%
• D. $7\frac{1}{3}$%

Answer 1

The correct option is C $8\frac{1}{3}$%

In the first case:
S.P. $=$ Rs. $120$ per kg
Profit $=20\%$
$\therefore$ C.P. $=120\times \frac{100}{120}=$ Rs. $100$ per kg
In the second Case:
S.P. of tea with $30\%$ profit for shopkeeper
$=100\times \frac{130}{100}=$ Rs. $130$ per kg
$\therefore$ S.P. of tea worth Rs. $120$ per kg increased by $10$.
$\therefore$ S.P. of tea worth Rs. $1$ per kg is increased by $\frac{10}{120}$.
$\therefore$ S.P. of tea worth Rs. $100$ per kg is increased by $\frac{10\times 100}{120}=$ Rs. $8\frac{1}{3}$
$\therefore$ Percentage increase in S.P. $=8\frac{1}{3}$ $\%$.