$A$ 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 $\%$).

$A$ shopkeeper sells one transistor for $Rs.\, 840$ at a gain of $20 \%$ and another for $Rs.\, 960$ at a loss of $4 \%$. His total gain or loss percent is

The list price of an article at a showroom is $Rs. 2000$ and it is being sold at successive discounts of $20 \%$ and $10 \%$. Its net selling price will be (in $Rs.$)

$A$ buys an article and sells it to $B$ at a profit of $10 \%$. $B$ sells it to $C$ gaining $20 \%$. If $C$ pays $₹ 924$,what amount did $A$ pay? (in $₹$)

$A$ 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 the chair in rupees is

Paras Health Care made $3000$ strips of vitamin tablets at a cost of $Rs. 4800$. The company gave away $1000$ strips of tablets to doctors as free samples. $A$ discount of $25\%$ is given on the printed price. Find the ratio of profit in $Rs.$ if the price is raised from $Rs. 3.25$ to $Rs. 4.25$ per strip and if at the latter price,samples to doctors were done away with.