A merchant buys $4000\, kg$ of wheat, one$-$fifth of which he sells at a gain of $5$ per cent, one$-$fourth at a gain of $10 \%$, one-half at a gain of $12$ percent, and the remainder at a gain of $16$ percent. If he had sold the whole at a gain of $11$ percent, he would have made $Rs.\, 72.80$ more. What was the cost price of the crop per kg? (in $Rs.$)

A shopkeeper sells a badminton racket, whose marked price is $Rs.\, 30$, at a discount of $15 \%$ and gives a shuttle cock costing $Rs.$ $1.50$ free with each racket. Even then he makes a profit of $20\%.$ His cost price per racket is (in $Rs$)

A fair price shopkeeper makes $10 \%$ profit on his goods. He lost $20 \%$ goods during theft. His. loss percent is

A shopkeeper has to sell $24\, Kg$ of sugar. He sells a part of these at a gain of $20 \%$ and the rest at a loss of $5 \% .$ If on the whole he earns a profit of $10 \%$, the amount of Sugar sold at a loss is in $Rs.$?

The marked price of a watch was $Rs.\, 720 .$ A man bought the same for $Rs.\, 550.80$ after getting two successive discounts, the first being $10 \% .$ What was the second discount rate? (in $\%$)

A shopkeeper purchased a chair marked at $RS.\, 600$ at two successive discounts of $15 \%$ and $20 \% .$ He spent $Rs.\, 28$ on transportation and sold the chair for $Rs.\,545.$ His gain percent was