A shopkeeper sells an article at a gain of $10 \% .$ Had he sold it at a loss of $20 \%,$ its selling price would have been $Rs.\,180$ less. What is the cost price of the article? (in $Rs.$)

A man buys a table and a chair for $Rs.\, 500.$ He sells the table at a loss of $10 \%$ and the chair at a gain of $10 \% .$ He still gains $Rs.\, 10$ on the whole. The cost price of chair in rupees is

If the discount of $10 \%$ is given on the marked price of a radio, the gain is $20 \%$. If the discount is increased to $20 \%,$ the gain is......$\%$

A fan is listed at $Rs.\, 1500$ and a discount of $20 \%$ is offered on the list price. What additional discount must be offered to the customer to bring the net price to $Rs$ $1104 ?$ (in $\%$)

A man bought orange at the rate of $8$ for $Rs.\,34$ and sold them at the rate of $12$ for $Rs.\,57.$ How many oranges should be sold to earn a net profit of $Rs.\,45?$

A shopkeeper gains the cost of $8$ metres thread by selling $40$ metres thread. Find his gain percent.