Mohandas mixes $10 \mathrm{kg}$ of oil purchased at $\mathrm{Rs}.15$ per $\mathrm{kg}$ with $5 \mathrm{kg}$ of oil purchased at $\mathrm{Rs}.10$ per $\mathrm{kg}.$ If he sells the mixture and gets $12.5\%$ Profit, what is the selling price of the oil per $\mathrm{kg}?$

When the price of a heater was increased by $20$ percent, the number of heaters sold decrease by $20$ percent. What was the effect on sales?

A man sold an article for $₹7200$ thus bearing a loss of $\frac{1}{4}th$ of this cost. The cost of the article is-

A man sold his watch for $₹190$ thus bearing a loss of $5\%$, The cost price of the watch is-

A trader bears a loss of $25\%$ by selling $40$ needles for a rupee. How many needles should he sell for a rupee in order to earn a profit of $20\%$?

What will be the gain or loss percent, if the cost price of $20$ articles equals the selling price of $30$ articles?

An article is sold at $25\%$ profit. If its C.P. and S.P. are increased by$₹20$ and $₹4$ respectively, the percentage of profit decreased by $15\%$. Find the cost price.

A hawker sells oranges at a profit of $40\%$. If he reduces the selling price of each orange by $30$ paise, he earns a profit of $25\%$. Find the cost price and the selling price of each orange after reduction in price?

The cost price of $10$ articles in equal to the selling price of $9$ articles. Find the profit percent.