$A$ person bought an article for $Rs. 240$. For how much should he sell it so as to lose $20\%$?

$A$ cab driver makes a profit of $20 \%$ on every trip when he carries $3$ passengers and the price of petrol is $Rs. 30$ a litre. Find the percentage profit for the same journey if he goes with four passengers per trip and the price of petrol reduces to $Rs. 24$ a litre? (in $\%$)
(Assume that revenue per passenger is the same in both the cases.)

$A$ vendor buys bananas at $9$ for $Rs. 8$ and sells at $8$ for $Rs. 9$. What will be the profit or loss (in $\%$)?

$A$ shopkeeper sold sarees at $Rs. 266$ each after giving a $5\%$ discount on the labelled price. Had he not given the discount,he would have earned a profit of $12\%$ on the cost price. What was the cost price of each saree? (in $Rs.$)

$A$ toothpaste labeled at $Rs. 80$ is sold for $Rs. 68$. The rate of discount is.......$\%$

$A$ sells an article to $B$ for $₹ 45,000$ losing $10 \%$ in the transaction. $B$ sells it to $C$ at a price which would have given a profit of $10 \%$ to $A$. By what per cent does $B$ gain?