At what price should a shopkeeper mark a radio that costs him $Rs. 1200$ in order that he may offer a discount of $20 \%$ on the marked price and still make a profit of $25 \% ?$

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 $30 \%$?

Aditya purchased $14$ shirts and $25$ pants at $Rs. 45$ and $Rs. 55$ respectively. What should be the approximate overall average selling price of a shirt and a pant so that a $40\%$ profit is earned?

The cost price of $100$ books is equal to the selling price of $60$ books. The gain or loss percentage will be:

$A$ shopkeeper allows a discount of $10\%$ on the marked price of an item but charges a sales tax of $8\%$ on the discounted price. If the customer pays $Rs. 3,402$ as the price including the sales tax,then the marked price is (in $Rs.$)

$A$ man sold his two cars for $Rs. 4.5$ lakh each. In the sale of the first car, he incurred $20\%$ profit, and in the sale of the second, he incurred $20\%$ loss. What is the total amount of profit or loss?