The cost price of an article is $64 \%$ of the marked price. Calculate the gain percent after allowing a discount of $12 \%$.

$A$ man invests $Rs. 21,000$ in shares of a company. He sells one-third of the total shares at a profit of $10\%$. However,he has to sell the remaining shares at a $5\%$ loss. Find his overall profit or loss percentage.

By selling an article for $Rs. 144$,a person gained such that the percentage gain equals the cost price of the article. The cost price of the article is (in $Rs.$):

$A$ cycle dealer offers a discount of $10 \%$ and still makes a profit of $26 \%$. What does he pay for a cycle whose marked price is $₹ 840$? (in $₹$)

Sanjay purchased a chair marked at $Rs. 800$ at $2$ successive discounts of $10 \%$ and $15 \%$ respectively. He spent $Rs. 28$ on transportation and sold the chair for $Rs. 800$. How much is his gain percentage (in $\%$)?

By selling an article for $Rs. 450$,a man loses $10\%$. The gain or loss percent if he sells it for $Rs. 540$ is: