Nitin bought some oranges at $Rs. 40$ a dozen and an equal number at $Rs. 30$ a dozen. He sold them at $Rs. 45$ a dozen and made a profit of $Rs. 480$. The total number of dozens of oranges he bought was:

The labelled price of a cupboard is $Rs. 6500$. The shopkeeper sold it by giving $5\%$ discount on the labelled price and earned a profit of $15\%$. What approximately is the cost price of the cupboard? (in $Rs.$)

The market price of an article is $Rs. 100$. If the article is sold at a discount of $10 \%$,then $35 \%$ profit is realized. How much loss or profit will be made if it is sold for $Rs. 30$ less than the market price?

$A$ sells an article to $B$ at a gain of $25 \%$,$B$ sells it to $C$ at a gain of $20 \%$,and $C$ sells it to $D$ at a gain of $10 \%$. If $D$ pays $₹ 330$ for it,how much did it cost $A$? (in $₹$)

Amit buys $5$ watches for $Rs. 9450$ and later sells them for $Rs. 9700$. How much profit does Amit make per watch in $Rs.$?

$A$ shopkeeper sold sarees at $Rs. 266$ each after giving a $5\%$ discount on the labelled price. Had he not given the discount,he would have earned a profit of $12\%$ on the cost price. What was the cost price of each saree? (in $Rs.$)