Mohan buys a watch for $Rs. 350$ and sells it for $Rs. 392$. Find out his percentage of profit.

$A$ rice trader buys $16$ quintals of rice for $Rs. 5632$. $20 \%$ of the rice is lost in transportation. At what rate should he sell the remaining rice to earn a $25 \%$ profit in $Rs.$ per quintal?

$A$ man purchased $150$ pens at the rate of $Rs. 12$ per pen. He sold $50$ pens at a gain of $10 \%$. The percentage gain at which he must sell the remaining pens so as to gain $15 \%$ on the whole outlay is........$\%$

$A$ shopkeeper allows a discount of $12.5 \%$ on the marked price of a certain article and makes a profit of $20 \%$. If the article costs the shopkeeper $Rs. 210$,then the marked price of the article will be (in $Rs.$)

By selling an article at $\frac{3}{4}$ of the marked price,there is a gain of $25 \%$. The ratio of the marked price to the cost price is:

$A$ shopkeeper bought $30\, Kg$ of wheat at the rate of $Rs.\, 45$ per $Kg$. He sold $40\%$ of the total quantity at the rate of $Rs.\, 50$ per $Kg$. Approximately,at what price per $Kg$ should he sell the remaining quantity to make $25\%$ overall profit? (in $Rs.$)