Profit and loss percentage

Always divide by the cost price — never by the selling price.

The question

An item costs ₹250 and sells for ₹300. What is the profit percentage?

The trick

Find the profit or loss in rupees, divide by the cost price, then multiply by 100.

Worked example

1Profit = 300 − 250 = ₹50
2Divide by the cost price: 50 ÷ 250 = 0.2
3Multiply by 100: 20%

So: 20%

Remember it like this

Cost price is always the boss. It sits under the line, every single time.

In the exam

The classic trap is dividing by the selling price. Before you write anything, circle the cost price in the question — that circled number is your denominator.

Why it works

Percentage always compares a change against the starting value, and in trade the starting value is what you paid — the cost price.

Explain this to my childGet the words to teach it, in your language

Try it yourself

0/3 correct

1
CP ₹400, SP ₹500. Profit % (number only)
CP ₹400, SP ₹500. Profit % (number only)
2
CP ₹600, SP ₹540. Loss % (number only)
CP ₹600, SP ₹540. Loss % (number only)
3
CP ₹80, SP ₹100. Profit % (number only)
CP ₹80, SP ₹100. Profit % (number only)