A dishonest dealer defrauds to the extent of $x \%$ in buying as well as selling his goods by using faulty weight. What will be the gain per cent on his outlay?

Ramesh purchased a bicycle for $Rs.\,5200$ and spent $Rs.\,800$ on its repairs. He had to sell it for $Rs.\,5500.$ Find out his profit or loss percent.

$'A'$ buys an article and sells it to $'B'$ at a profit of $10 \%,{ }^{\prime} B ^{\prime}$ sells it to $'C ^{\prime}$ gaining $20 \% .$ If $'C ^{\prime}$ gives $RS.\,924,$ what amount did $'A'$ give? (in $Rs.$)

A man bought some fruits at the rate of $16$ for $Rs. 24$ and sold them at the rate of $8$ for $Rs$ $18.$ What is the profit percent? 

A trader mixes three varieties of groundnuts costing $Rs. \,50, Rs.\, 20$ and $Rs.\, 30$ per $k g$ in the ratio $2: 4: 3$ in terms of weight and sells the mixture at $Rs.\, 33$ per $kg .$ What percentage of profit does he make?

A person sells $36$ oranges per $Rs.\, 1$ and makes a loss of $4 \% .$ Find how many oranges per $Rs$ to be sold to have a gain of $8 \% ?$