Successive discounts of $20 \%$ and $10 \%$ are given on an item marked at $Rs. 700$. Find the selling price (in $Rs.$).

$A$ dealer marks a washing machine for $Rs.\, 7500$ and allows a discount of $6 \%$ on it. Find its selling price in $Rs.$

$Rs. 20$ is the true discount on $Rs. 260$ due after a certain time. What will be the true discount on the same amount due after half of the earlier time,the rate of interest being the same? (in $Rs.$)

$A$ dealer allows a discount of $15 \%$. $A$ customer pays an amount of $Rs. 318.75$ for an article. At what price is the article listed? (in $Rs.$)

What was the rate of discount if a computer with a marked price of $Rs. 30,000$ was sold for $Rs. 28,000$? (in $\%$)

Ticket for an adult is $Rs. 1500$ and that of a child is $Rs. 800$. One child goes free with two adults. If a group has $25$ adults and $12$ children,what is the discount the group gets? (in $\%$)