A trader buys $500\, kg$ of cotton for $Rs.\, 9,000.10 \%$ of this cotton is spoiled due to rain. At what rate ($Rs./ kg$) should he sell the rest to earn $10 \%$ profit?

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?

The marked price of a clock is $Rs.\,3200.$ It is to be sold at $Rs$ $2448$ at two successive discounts. If the first discount is $10 \%$, then the second discount is.........$\%$

A shopkeeper marks his goods at $40 \%$ above their cost price. He is able to sell $\frac{3}{4}$ th of his goods at this price, and the remaining at $40 \%$ discount. Assuming that the shopkeeper is able to sell the goods he buys, find his loss or gain as $\%$ of the whole transaction.

The ratio of cost price and selling price of an article is $25: 26 .$ The percent of profit will be

Meenal purchased a car for $Rs.\, 2,50,000$ and sold it for $Rs.\, 3,48,000 .$ What is the per cent profit she made on the car?