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

$A$ bakery bakes cakes with the expectation that it will earn a profit of $40 \%$ by selling each cake at the marked price. During delivery to the showroom, $16 \%$ of the cakes were completely damaged and could not be sold. $24 \%$ of the cakes were slightly damaged and were sold at $80 \%$ of the cost price. The remaining $60 \%$ of the cakes were sold at the marked price. What is the percentage profit on the whole consignment (in $\%$)?

On selling $17$ balls at $₹720,$ there is a loss equal to the cost price of $5$ balls. The cost price of a ball is

$A$ dishonest dealer uses a scale of $90 \, cm$ instead of a metre scale and claims to sell at cost price. His profit percentage is:

Seema purchased an item for $Rs.\, 9600$ and sold it for a loss of $5\%$. From that money, she purchased another item and sold it for a gain of $5\%$. What is her overall gain or loss?

$A$ man bought apples at the rate of $8$ for $Rs. 34$ and sold them at the rate of $12$ for $Rs. 57$. How many apples should be sold to earn a net profit of $Rs. 45$?