On an order of $5$ dozen boxes of a consumer product,a retailer receives an extra dozen free. This is equivalent to allowing him a discount of........$\%$

$A$ 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?

$A$ cloth dealer professes to sell cotton at cost price, but uses a meter scale having a length of $80 \, cm$ only and charges for a full meter. Find his gain percent.

Sudeep buys two $CDs$ for $Rs. 380$ and sells one at a loss of $22 \%$ and the other at a gain of $12 \%$. If both the $CDs$ are sold at the same price,then the cost price of the two $CDs$ is (in $Rs.$)

$A$ sells a suitcase to $B$ at $10\%$ profit. $B$ sells it to $C$ at $30\%$ profit. If $C$ pays $₹ 2,860$ for it,then the price at which $A$ bought it is (in $₹$):

$A$ man buys a cycle for $Rs. 1400$ and sells it at a loss of $15 \%$. What is the selling price of the cycle? (in $Rs.$)