Some articles were bought at $6$ articles for $Rs. 5$ and sold at $5$ articles for $Rs. 6$. The gain percent is: (in $\%$)

By selling $80$ ball pens for $₹ 140$,a retailer loses $30 \%$. How many ball pens should he sell for $₹ 104$ so as to make a profit of $30 \% ?$

By selling $80$ ball pens for $₹ 140$,a retailer loses $30 \%$. How many ball pens should he sell for $₹ 104$ so as to make a profit of $30 \%$?

The selling price of a glass is $Rs. 1965$ and the loss percentage is $25 \%$. If the selling price is $Rs. 3013$,then what will be the profit percentage (in $\%$)?

$A$ reduction of $10 \%$ in the price of rice enables a person to obtain $25 \text{ kg}$ more for $Rs. 2250$. Find the reduced price per $\text{kg}$ of the rice (in $Rs.$).

$A$ shopkeeper marks his goods at $40 \%$ above their cost price. He is able to sell $\frac{3}{4}$ of his goods at this price,and the remaining at $40 \%$ discount. Assuming that the shopkeeper is able to sell all the goods he buys,find his overall gain or loss percentage.