If the selling price of $50$ articles is equal to the cost price of $40$ articles, then the loss or gain percent is 

A man sells an article at a loss of $5 \% .$ If he had bought it at $20 \%$ more and sold it for $Rs.\,115$ less, he would have made a loss of $40 \% .$ Find the cost price of the article.

A merchant advertises $10 \%$ off on the items bought from his store. The total discount got by a customer who bought a cooker worth $Rs.\,650,$ a heater worth $Rs.\,500$ and a bag worth $Rs.\,65$ is (in $Rs.$)

Kamya purchased an item for $Rs.\, 46,000$ and sold it at aloss of $12$ percent. With that amount she purchased another item which he sold at a gain of $12 \% .$ What was her overall gain/loss?

A shopkeeper sells goods at $10 \%$ loss on cost price, but uses $20 \%$ less weight. What is his profit or loss percentage?