The cost price of $100$ books is equal to the selling price of $60$ books. The gain percentage or loss percentage is:

$A$ fan is listed at $Rs. 1500$ and a discount of $20 \%$ is offered on the list price. What additional discount must be offered to the customer to bring the net price to $Rs. 1104$? (in $\%$)

$A$ sells a bicycle to $B$ at a profit of $20 \%$ and $B$ sells it to $C$ at a profit of $25 \%$. If $C$ pays $Rs. 1500$,what did $A$ pay for it in $Rs.$?

$A$ shopkeeper professes to sell his goods at cost price but uses a weight of $800 \text{ g}$ instead of a $1 \text{ kg}$ weight. His profit percentage is:

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 buys a cycle for $Rs. 1400$ and sells it at a loss of $15 \%$. What is the selling price of the cycle? (in $Rs.$)