Some articles were bought at $6$ articles for $Rs. 5$ and sold at $5$ articles for $Rs. 6$. The gain percent is: (in $\%$)

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

By selling an article at $80 \%$ of its marked price,a shopkeeper makes a loss of $10 \%$. What will be the profit percentage if he sells it at $95 \%$ of its marked price (in $\%$)?

$A$ shopkeeper sells notebooks at the rate of $Rs.\, 45$ each and earns a commission of $4 \%$. He also sells pencil boxes at the rate of $Rs.\, 80$ each and earns a commission of $20 \%$. How much total commission will he earn in two weeks if he sells $10$ notebooks and $6$ pencil boxes a day? (in $Rs.$)

By selling a book for $Rs. 360$,$20\%$ profit was earned. What is the $CP$ of the book in $Rs.$?

An article was purchased for $Rs. 78,350$. Its price was marked up by $30 \%$. It was sold at a discount of $20 \%$ on the marked-up price. What was the profit percent on the cost price (in $\%$)?