The printed price of an article is $40 \%$ higher than its cost price. What is the discount rate so that the seller gains a $12 \%$ profit?

By selling an article for $Rs. 21$,a man incurs a loss such that the percentage loss is equal to the cost price. The cost price of the article is (in $Rs.$):

By selling an article for $Rs. 384$,a trader gains $20 \%$. Find the cost price of the article.

$60 \%$ of the cost price of an article is equal to $50 \%$ of its selling price. Then the percentage of profit or loss on the cost price is

Hemant purchased $120$ rims of paper at $Rs. 80$ per rim. He spent $Rs. 280$ on transportation,paid octroi at the rate of $40$ paise per rim,and paid $Rs. 72$ to the coolie. If he wants to have a gain of $8 \%$,the selling price per rim must be (in $Rs.$)

$A$ single discount,equivalent to a successive discount of $40 \%$ and $30 \%$ is in $\%$?