$A$ man sold two cows at $Rs. 1995$ each. On one he lost $10\%$ and on the other he gained $10\%$. What is his gain or loss percent (in $\%$)?

$A$ shopkeeper sold an article for $Rs. 400$ after giving a $20\%$ discount on the labelled price and made a $30\%$ profit on the cost price. What would have been the percentage profit,had he not given the discount (in $\%$)?

$A$ person sells $36$ oranges for $₹ 1$ and makes a loss of $4 \%$. Find how many oranges per $₹ 1$ should be sold to have a gain of $8 \%$.

$A$ dealer buys an article listed at $Rs. 100$ and gets successive discounts of $10\%$ and $20\%$. He spends $10\%$ of the cost price on transportation. At what price should he sell the article to earn a profit of $15\%$? (in $Rs.$)

$A$ dairyman pays $Rs. 6.40$ per litre of milk. He adds water and sells the mixture at $Rs. 8$ per litre,thereby making $37.5\%$ profit. The proportion of water to milk received by the customers is

$A$ shopkeeper sells one transistor for $Rs.\, 840$ at a gain of $20 \%$ and another for $Rs.\, 960$ at a loss of $4 \%$. His total gain or loss percent is