$A$ book seller allowed $10 \%$ discount on the printed price. He gets a $30 \%$ commission from the publisher. His profit percentage will be:

The selling price of a radio was $Rs. 255$ when $15 \%$ discount was allowed. Then the marked price of the radio was (in $Rs.$)

$A$ man bought a motorcycle for $Rs. 32500$. He sold it for $Rs. 35000$,allowing the buyer a $6$ months credit. If the money is worth $4\%$ per annum,the gain percent is (in $\%$):

$A$ man buys a single apple for $Rs. 25$. If he were to buy a dozen apples,he would have to pay a total amount of $Rs. 250$. What would be the approximate percent discount he would get on buying a dozen apples?

If after giving a discount of $18 \%$,a book is sold for $Rs. 1599$,what will be the marked price (in $Rs.$) of the book?

Find the present worth $(P.W.)$ and the true discount $(T.D.)$ reckoning $6 \%$ per annum simple interest of $Rs. 176$ due in $20 \text{ months}$ time. (in $Rs.$)