$A$ man sold his two horses for $Rs. 770$ each. On one he gained $10\%$ and on the other he lost $10\%$. The average gain or loss percentage is:

On a certain item,the profit is $150 \%$. If the cost price increases by $25 \%$,what will be the new profit margin (in $\%$)?

$A$ businessman allows a discount of $10 \%$ on the marked price. What percent above the cost price must he mark his goods to make a profit of $17 \% ?$

By selling an article for $Rs. 450$,a man loses $10\%$. The gain or loss percent if he sells it for $Rs. 540$ is:

With a $5 \%$ discount on the cost of sugar,a buyer could purchase $2 \text{ kg}$ more sugar for $Rs. 608$. What is the initial selling price of sugar per kg?

$A$ person earns $15 \%$ on an investment but loses $10 \%$ on another investment. If the ratio of the two investments is $3:5$,what is the gain or loss percentage on the two investments taken together (in $\%$)?