Mahesh purchased $25\, kg$ of rice at $Rs. 32$ per $kg$ and $15\, kg$ of rice at $Rs. 36$ per $kg.$ He mixed the two varieties of rice and sold it at $Rs. 40.20$ per $kg.$ What is the percent profit earned (in $\%$)?

$A$ fruit seller bought $240$ bananas at the rate of $Rs. 48$ per dozen. He sells half of them at the rate of $Rs. 5$ per banana. $\frac{1}{6}$ of the remaining bananas are found to be rotten. At what price per banana must he sell the remaining bananas to get a profit of $25\%$ on his entire investment?

The labelled price of a cupboard is $Rs. 6500$. The shopkeeper sold it by giving $5\%$ discount on the labelled price and earned a profit of $15\%$. What approximately is the cost price of the cupboard? (in $Rs.$)

Oil equal to $20 \%$ of the weight of groundnut is extracted in a mill. The matter left after extraction is sold as cattle feed at the rate of $Rs. 12.5$ per $kg$. The groundnuts are bought at $Rs. 20$ per $kg$ and the processing cost is $Rs. 5$ per $kg$. At what price ($Rs.$ per $kg$) should the oil be sold to earn $20 \%$ profit on total costs (Total cost $=$ cost of groundnuts and processing costs)?

The marked price of a tape recorder is $Rs. 12,600$. $A$ festival discount of $5 \%$ is allowed on it. Further,for cash payment,a second discount of $2 \%$ is given. The cash payment,in rupees,to be made for buying it is: (in $.60$)

The ratio of cost price and selling price of an article is $25:26$. The percent of profit will be