The ratio of the cost price of an item and the profit gained while selling the item is 4 : 1. What is the profit percentage?

The ratio of the cost price of an item and the profit gained while selling the item is 4 : 1.

Let's assume the cost price of an item and the profit gained while selling the item is '4y' and 'y' respectively.

Selling price of the item = 4y+y = 5y

Profit percentage = $$\frac{\left(selling\ price-cost\ price\right)}{cost\ price}\times100$$

= $$\frac{\left(5y-4y\right)}{4y}\times100$$

= $$\frac{y}{4y}\times100$$

= $$\frac{1}{4}\times100$$

= 25%