$A$ tradesman gives $4 \%$ discount on the marked price and gives $1$ book free for buying every $15$ books and thus gains $35 \%$. The marked price is increased above the cost price by (approx.) (in $\%$).

$A$ dealer fixed the price of an article $40 \%$ above the cost of production. While selling it,he allows a discount of $20 \%$ and makes a profit of $Rs. 48$. The cost of production (in $Rs.$) of the article is:

$A$ sells an article to $B$ at a profit of $20 \%$ and $B$ sells it to $C$ at a loss of $10 \%$. If $C$ pays $Rs. 540$ for it,at what price did $A$ buy?

Maninder bought two horses at $Rs. 40,000$ each. He sold one horse at $15\%$ gain, but had to sell the second horse at a loss. If he had suffered a loss of $Rs. 3,600$ on the whole transaction, then the selling price of the second horse is (in $Rs.$)

$A$ man sold two watches for $Rs. 3750$ each. On one he gained $5 \%$,and on the other,he lost $5 \%$. What was his total gain or loss percentage?

The printed price of an article is $40 \%$ higher than its cost price. What is the discount rate so that the seller gains a $12 \%$ profit?