An article is sold at a gain of $15 \%$. Had it been sold for $₹ 27$ more,the profit would have been $20 \%$. The cost price of the article is (in $₹$):

Nutan bought $30$ dozens of oranges for her juice stall in the school fair. She paid $Rs. 8$ per dozen of oranges. She also had to pay $Rs. 500$ as the stall fee to the school authorities. She calculated that each glass of juice would need $3$ oranges. How much should she charge per glass of juice so as to make $20 \%$ profit in $Rs$?

$A$ man sold a cow at a loss of $12 \%$. If he had sold it at a gain of $6 \%$,he would have received $₹ 72$ more. What was the cost price of the cow?

$A$ shopkeeper gains $17 \%$ after allowing a discount of $10 \%$ on the marked price of an article. Find his profit percent if the article is sold at the marked price allowing no discount. (in $\%$)

$A$ shopkeeper cheats to the extent of $10 \%$ while buying as well as selling by using false weights. His total gain percentage is:

The cost price of $6$ pens is equal to the selling price of $4$ pens. Find the profit percent. (in $\%$)