A man purchases some oranges at the rate of $3$ for $Rs.\,40$ and the same quantity at $5$ for $Rs.\, 60.$ If he sells all the oranges at the rate of $3$ for $Rs.\, 50,$ find his gain or loss percent (to the nearest integer).

A retailer offers the following discount schemes for buyers on an article

$I.$ Two successive discounts of $10 \%$

$II.$ A discount of $12 \%$ followed by a discount of $8 \%$

$III.$ Successive discounts of $15 \%$ and $5 \%$

$IV.$ A discount of $20 \%$

The selling price will be minimum under the scheme

If selling price is doubled, the profit triples. Find the profit percent

Selling price of a chair is $Rs.$ $1386 .$ If loss percent is $23 \%$ then what is the cost price (in $Rs.$) of chair?

A pair of article, was bought for $Rs.\, 37.40$ at a discount of $15 \% .$ What must be the marked price of each of the articles?

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