The banker's discount on a certain sum of money is $Rs. 84$ and the true discount on the same sum for the same time is $Rs. 70$. The sum due is (in $Rs.$)

$Rs.\, 20$ is the true discount on $Rs.\, 210$ due after a certain time. What will be the true discount on the same sum due after half of the former time,the rate of interest being the same? (in $Rs.$)

Ramesh marks his goods $30 \%$ above cost price. If he sells the item for $Rs. 910$ after allowing a discount of $15 \%$,find his cost price (in $Rs.$).

The difference between a discount of $40 \%$ on $Rs. 500$ and two successive discounts of $36 \%$ and $4 \%$ on the same amount is (in $Rs.$)

$A$ retailer gets a discount of $40 \%$ on the printed price of an article. The retailer sells it at the printed price. His gain percent is

The holder of a bill for $Rs. 17850$ nominally due on $May 21, 1991$ received $Rs. 357$ less than the amount of the bill by having it discounted at $5 \%$. When was it discounted?