There would be a $10 \%$ loss,if rice is sold at $Rs. 54$ per $kg$. To earn a profit of $20 \%$,the price of rice per $kg$ will be (in $Rs.$)

On a certain item,the profit is $150 \%$. If the cost price increases by $25 \%$,what will be the new profit margin (in $\%$)?

$A$ trader mixes $26 \text{ kg}$ of rice at $Rs. 20$ per $\text{kg}$ with $30 \text{ kg}$ of rice of another variety at $Rs. 36$ per $\text{kg}$ and sells the mixture at $Rs. 30$ per $\text{kg}$. His profit percent is:

$A$ shopkeeper allows a discount of $12.5 \%$ on the marked price of a certain article and makes a profit of $20 \%$. If the article costs the shopkeeper $Rs. 210$,then the marked price of the article will be (in $Rs.$)

If the selling price of $50$ articles is equal to the cost price of $40$ articles,then the loss or gain percent is:

Sonal buys mangoes at the rate of $3 \, \text{kg}$ for $Rs. 21$ and sells them at $5 \, \text{kg}$ for $Rs. 50$. To earn a profit of $Rs. 102$, he must sell how many mangoes in $\text{kg}$?