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

The cost price of an article is $64 \%$ of the marked price. Calculate the gain percent after allowing a discount of $12 \%$.

$A$ shopkeeper sells $20$ pencils for the same amount of money as he paid for $25$ pencils. What is his gain percent?

$A$ shopkeeper purchased $150$ identical pieces of furniture at the rate of $Rs. 250$ each. He spent an amount of $Rs. 2500$ on packing. He fixed the price of each furniture at $Rs. 320$. However,he decided to give a discount of $5 \%$ on the labeled price. What is the percent profit earned by him (in $\%$)?

Surbhi bought a combined total of $25$ i-pads and i-phones. She marked up the i-pad by $20 \%$ on the cost price,while each i-phone was marked up by $Rs. 2000$. She was able to sell $75 \%$ of the i-pads and $2$ i-phones and make a profit of $Rs. 49000$. The remaining i-pads and $3$ i-phones could not be sold by her. Find her overall profit or loss if she gets no return on unsold items and it is known that an i-phone costs $50 \%$ of an i-pad.

$A$ trader marked the price of his commodity so as to include a profit of $25 \%$. He allowed a discount of $16 \%$ on the marked price. His actual profit was (in $\%$):