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

$A$ retailer marks up his goods by $150 \%$ and offers a $40 \%$ discount. What will be the selling price (in $Rs.$) if the cost price is $Rs.\, 800$?

$A$ trader allows a discount of $15 \%$ on a trolley bag having a list price of $Rs. 1360$ and earns a profit of $15.6 \%$. What is the cost price (in $Rs.$) of the trolley bag?

If $Rs. 10$ is allowed as true discount on a bill of $Rs. 110$ due at the end of a certain time,then the discount allowed on the same amount due at the end of double the time is (in $Rs.$)

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

If the simple interest on $Rs. 2000$ at $5\%$ $p.a.$ is equal to the true discount on $Rs. 2500$ for the same time and at the same rate,the time is (in $years$)