If the cost price of $20$ tables is equal to the selling price of $25$ tables,find the loss percentage. (in $\%$)

$A$ shopkeeper sells an article at a gain of $10 \%$. Had he sold it at a loss of $20 \%$,its selling price would have been $Rs. 180$ less. What is the cost price of the article? (in $Rs.$)

The cost price of an article is $64 \%$ of the marked price. The gain percentage after allowing a discount of $12 \%$ on the marked price is........$\%$

$A$ man purchased $120$ reams of paper at $Rs. 80$ per ream. He spent $Rs. 280$ on transportation,paid octroi at the rate of $40$ paise per ream,and paid $Rs. 72$ to a porter. In order to gain $8\%$ profit,he must sell each ream of paper for (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?

Mohit lost $18 \%$ by selling a bicycle for $Rs. 1230$. What percent shall he gain or loss by selling it for $Rs. 1600$?