The banker's gain of a certain sum due $2$ $years$ hence at $12 \frac{1}{2} \%$ per annum is $Rs.\,36$. The present worth is (in $Rs.$)

$A$ watch dealer pays $10 \%$ customs duty on a watch which costs $Rs.\, 500$ abroad. He desires to make a profit of $20 \%$ after giving a discount of $25 \%$ to the buyer. The marked price should be (in $Rs.$)

The marked price of an item is $Rs. 900$. On the purchase of $2$ items,the discount is $16\%$,and on the purchase of $5$ items,the discount is $44\%$. If Raksha buys $7$ items,what is the effective discount percentage?

The present worth of a sum of money due for $146 \text{ days}$ at $5 \%$ is $Rs. 400$. The sum due is (in $Rs.$)

The present worth of $Rs. 220.50$ due in $2$ years reckoning compound interest at $5 \%$ per annum is (in $Rs.$):

Ramesh marks his article at $Rs. 6000$ and after allowing a discount of $20 \%$, he still earns $60 \%$ profit. What is the cost price (in $Rs.$) of the article?