An article is marked $40 \%$ above the cost price and a discount of $30 \%$ is allowed. What is the gain or loss percentage?

Ticket for an adult is $Rs. 1500$ and that of a child is $Rs. 800$. One child goes free with two adults. If a group has $25$ adults and $12$ children,what is the discount the group gets? (in $\%$)

$A$ dealer purchased an article for $Rs. 900$ and fixes the list price in such a way that he gains $20\%$ after allowing $10\%$ discount. What is the list price (in $Rs.$)?

$Rs. 20$ is the true discount on $Rs. 260$ due after a certain time. What will be the true discount on the same amount due after half of the earlier time,the rate of interest being the same? (in $Rs.$)

$A$ shopkeeper gives two successive discounts of $7 \%$ each on the marked price of $Rs.\, 20,000$ of an article. The selling price of the article is (in $Rs.$):

The price of a chair is $Rs.\, 500$. It has been sold at two successive discounts of $10\%$ each. What is its selling price? (in $Rs.$)