If on selling $12$ notebooks,a seller makes a profit equal to the selling price of $4$ notebooks,what is his percent profit?

Find $CP$ when $SP = Rs. 40.60$ and $\text{gain} = 16\%$.

Gita buys a plot of land for $Rs. 96,000$. She sells $\frac{2}{5}$ of it at a loss of $6\%$. She wants to make a profit of $10\%$ on the whole transaction by selling the remaining land. The gain percentage on the remaining land is

$A$ $TV$ set is being sold for $Rs. x$ in Chandigarh. $A$ dealer went to Delhi and bought the $TV$ at a $20\%$ discount (from the price of Chandigarh). He spent $Rs. 600$ on transport. Thus,he sold the set in Chandigarh for $Rs. x$,making a $14 \frac{2}{7}\%$ profit. What was $x$ in $Rs.?$

Abhishek makes a profit of $Rs. 110$ if he sells a certain number of pens at the price of $Rs. 2.5$ per pen and incurs a loss of $Rs. 55$ if he sells the same number of pens for $Rs. 1.75$ per pen. How many pens does Abhishek have?

Abhishek purchased $140$ shirts and $250$ trousers at $Rs. 450$ and $Rs. 550$ respectively. What should be the overall average selling price of shirts and trousers so that $40 \%$ profit is earned? (in $Rs.$) (rounded off to the next integer)