$A$ shopkeeper sold chairs at $Rs. 2139$ each after giving a $7 \%$ discount on the labelled price. Had he not given the discount, he would have earned a profit of $15 \%$ on the cost price. What was the cost price of each chair? (in $Rs.$)

The cost price of $6$ pens is equal to the selling price of $4$ pens. Find the profit percent. (in $\%$)

$A$ man had a certain amount with him. He spent $20\%$ of that to buy an article and $5\%$ of the remaining on transport. Then he gifted $Rs. 120$. If he is left with $Rs. 1,400$,the amount he spent on transport is (in $Rs.$)

The cost price of $20$ articles is the same as the selling price of $x$ articles. If the profit is $25 \%$,then the value of $x$ is:

Paras Health Care made $3000$ strips of vitamin tablets at a cost of $Rs. 4800$. The company gave away $1000$ strips of tablets to doctors as free samples. $A$ discount of $25\%$ is given on the printed price. Find the ratio of profit in $Rs.$ if the price is raised from $Rs. 3.25$ to $Rs. 4.25$ per strip and if at the latter price,samples to doctors were done away with.

The marked price of a clock is $Rs. 3200$. It is sold at $Rs. 2448$ after two successive discounts. If the first discount is $10 \%$,then the second discount is.........$\%$