$A$ buys an article and sells it to $B$ at a profit of $10 \%$. $B$ sells it to $C$ gaining $20 \%$. If $C$ pays $₹ 924$,what amount did $A$ pay? (in $₹$)

If a commission at the rate of $10 \%$ is given to a bookseller on the marked price of a book by the publisher,the publisher gains $20 \%$. If the commission is increased to $15 \%$ then the gain percent would be

By selling $80$ ball pens for $₹ 140$,a retailer loses $30 \%$. How many ball pens should he sell for $₹ 104$ so as to make a profit of $30 \%$?

Profit obtained on selling an article for $Rs. 310$ is equal to the loss incurred on selling that article for $Rs. 230$. What will be the loss percentage when selling price is $Rs. 180$?

$A$ cloth merchant says that due to a slump in the market,he sells cloth at a $10 \%$ loss,but he uses an inaccurate metre scale and actually gains $15 \%$. Find out the actual length of the scale (in $cm$).

$A$ trader marks the price of his goods $25 \%$ above the cost price but allows a $12.5 \%$ discount for cash payment. If he sells the goods for $Rs. 875$,find the cost price of the goods (in $Rs.$).