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 $Rs.$)

The profit earned by selling an article for $Rs. 900$ is double the loss incurred when the same article is sold for $Rs. 450$. At what price should the article be sold to make $25\%$ profit?

The marked price of a bed is $Rs. 2400$. The shopkeeper gives successive discounts of $10 \%$ and $X \%$ to the customer. If the customer pays $Rs. 1836$ for the bed,then find the value of $X$ in $\%$.

$A$ shopkeeper sells $25$ articles at $Rs. 45$ per article after giving a $10 \%$ discount and earns a $50 \%$ profit. If no discount is given,the profit percentage gained is......$\%$

Ravi purchases $90$ pens and sells $40$ pens at a gain of $10 \%$ and $50$ pens at a gain of $20 \%$. Had he sold all of them at a uniform profit of $15 \%$,he would have got $Rs. 40$ less. Find the cost price of each pen in $Rs$.

$A$ shopkeeper sells notebooks at the rate of $Rs. 457$ each and earns a commission of $4\%$. He also sells pencil boxes at the rate of $Rs. 80$ each and earns a commission of $20\%$. How much total commission will he earn in two weeks if he sells $10$ notebooks and $6$ pencil boxes a day?