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 marks the price of his goods $25 \%$ above the cost price but allows a $12.5 \%$ discount for cash payment. If he sells the goods for $Rs. 875$,find the cost price of the goods (in $Rs.$).

Aditya bought a scooter for a certain sum of money. He spent $15 \%$ of the cost price on repairs and sold it for a profit of $Rs. 1104$. What did he spend on repairs if the profit he earned was $20 \%$?

By selling an article at $80 \%$ of its marked price,a shopkeeper makes a loss of $10 \%$. What will be the profit percentage if he sells it at $95 \%$ of its marked price (in $\%$)?

If the selling price is doubled,the profit triples. Find the profit percent.

$A$ loss of $19 \%$ gets converted into a profit of $17 \%$ when the selling price is increased by $Rs. 162$. The cost price of the article is (in $Rs.$)