If a commission at the rate of $10 \%$ is given to a bookseller on the marked price of a book by the publisher,the publisher gains $20 \%$. If the commission is increased to $15 \%$ then the gain percent would be

$A$ single discount,equivalent to a successive discount of $40 \%$ and $30 \%$ is in $\%$?

The marked price of a bed is $Rs. 2400$. The shopkeeper gives successive discounts of $10 \%$ and $X \%$ to the customer. If the customer pays $Rs. 1836$ for the bed,then find the value of $X$ in $\%$.

$A$ shopkeeper sells rice at $10 \%$ profit and uses weight $30 \%$ less than the actual measure. His gain percent is

An $Ox$ and a carriage together cost $Rs. 8000$. The ox is sold at a profit of $10\%$ and the carriage is sold at a loss of $10\%$. If the total profit made is $2.5\%$,then what is the cost price of the ox? (in $Rs.$)

$A$ retailer offers the following discount schemes for buyers on an article:
$I.$ Two successive discounts of $10 \%$
$II.$ $A$ discount of $12 \%$ followed by a discount of $8 \%$
$III.$ Successive discounts of $15 \%$ and $5 \%$
$IV.$ $A$ discount of $20 \%$
The selling price will be minimum under the scheme: