$A$ trader sold an article at a gain of $20 \%$. Had he purchased it for $40 \%$ more and sold for $Rs. 24$ less,he would have incurred a loss of $20 \%$. What is the cost price (in $Rs.$) of the article?

$A$ fan costing $Rs. 1200$ is being sold for $Rs. 1500$. What is the profit percent?

$A$ shopkeeper sold an article offering a discount of $5 \%$ and earned a profit of $23.5 \%$. What would have been the percentage of profit earned if no discount had been offered?

$A$ person purchased a saree for $Rs. 7710$ after availing a net discount of $Rs. 1285$. The percentage of discount,the saree shop offers,is

$A$ shopkeeper sells one transistor for $Rs.\, 840$ at a gain of $20 \%$ and another for $Rs.\, 960$ at a loss of $4 \%$. His total gain or loss percent is

$A$ 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.)