What will be the net discount (in $percentage$) after two successive discounts of $50 \%$ and $50 \% ?$

If the shopkeeper sells an item at $Rs. 960$ which is marked as $Rs. 1200$, what is the discount he is offering? (in $\%$)

An article is marked $40 \%$ above the cost price and a discount of $30 \%$ is allowed. What is the gain or loss percentage?

The present worth of $Rs. 920$ due at the end of $3$ years at $5\%$ simple interest per annum 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 true discount on a certain bill due for nine months at $4 \%$ simple interest is $Rs.\, 150$. Find the amount of the bill (in $Rs.$).