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 $Rs.$).

If a shopkeeper allows a $20 \%$ discount on his advertised price and makes a profit of $25 \%$ on his outlay,what is the advertised price (in $Rs.$) on which he gains $Rs. 6000$?

The $B.G.$ on a certain sum due in $5 \text{ years}$ is $\frac{3}{23}$ of $B.D.$ Here,the rate of interest is (in $\%$):

$A$ man bought a motorcycle for $Rs. 32500$. He sold it for $Rs. 35000$,allowing the buyer a $6$ months credit. If the money is worth $4\%$ per annum,the gain percent is (in $\%$):

The price of a shirt after $15\%$ discount is $Rs.\,119$. What was the marked price of the shirt before the discount? (in $Rs.$)

$Rs. 21$ is the true discount on $Rs. 371$ for a certain time at a certain rate of interest. If the rate of interest is kept the same,the true discount on the same sum for double that time will be (in $Rs.$)