By selling an article for $Rs. 21$,a man incurs a loss such that the percentage loss is equal to the cost price. The cost price of the article is (in $Rs.$):

$A$ trader sells rice at a profit of $5 \%$ and uses a weight which is $25 \%$ less. Find the total percentage gain.

There is a profit of $20 \%$ on the cost price of an article. The per cent of profit, when calculated on the selling price is.......$\%$

$A$ merchant advertises $10 \%$ off on the items bought from his store. The total discount obtained by a customer who bought a cooker worth $Rs. 650$,a heater worth $Rs. 500$,and a bag worth $Rs. 65$ is (in $Rs.$): (in $.50$)

$A$ trader marks his goods $40 \%$ above the cost price and allows a discount of $25 \%$. The profit he makes,is in $\%$:

If the selling price of an article is $\frac{4}{3}$ of its cost price,the profit percentage in the transaction is: (in $\%$)