👁 Preview — Study, Practice and Revise are open; mock tests and the rest of the syllabus unlock on subscription. Unlock all · ₹4,999
← Back to Number System and Arithmetic
Study mode

Profit and Loss

Introduction to Profit and Loss

Every day, we buy and sell goods or services. Whether you are shopping at a market, running a business, or even participating in a competitive exam, understanding how profit and loss work is essential. Profit and loss help us understand whether we are gaining or losing money in a transaction.

In this section, we will learn about the key terms like cost price and selling price, and how to calculate profit and loss. These concepts are closely related to percentages and basic arithmetic, which you have already studied. By mastering profit and loss, you will be able to solve many practical problems and perform well in exams.

Basic Definitions and Relationships

Let's start by defining the important terms:

  • Cost Price (CP): The price at which an item is bought. For example, if you buy a book for Rs.500, then Rs.500 is the cost price.
  • Selling Price (SP): The price at which the item is sold. If you sell the same book for Rs.600, then Rs.600 is the selling price.
  • Profit: When the selling price is more than the cost price, the difference is called profit. It means you earned money.
  • Loss: When the selling price is less than the cost price, the difference is called loss. It means you lost money.

Understanding these terms is the first step to solving profit and loss problems.

Cost Price (CP) Selling Price (SP) Profit (SP - CP) Loss (CP - SP)

Note: If the selling price is less than the cost price, the profit area disappears, and instead, the loss area appears to the left of CP.

Profit and Loss Percentages

Profit and loss are often expressed as percentages to understand the gain or loss relative to the cost price. This helps compare profits or losses across different transactions easily.

  • Profit Percentage: It tells us how much profit we made as a percentage of the cost price.
  • Loss Percentage: It tells us how much loss we incurred as a percentage of the cost price.
Key Concept

Profit and Loss Percentages

Profit or loss expressed as a percentage of the cost price helps compare transactions of different sizes.

Key Formulas

Here are the essential formulas you will use to solve profit and loss problems:

Formula Name Formula Variables
Profit \( \text{Profit} = SP - CP \) SP = Selling Price, CP = Cost Price
Loss \( \text{Loss} = CP - SP \) CP = Cost Price, SP = Selling Price
Profit Percentage \( \text{Profit \%} = \left( \frac{\text{Profit}}{CP} \right) \times 100 \) Profit = SP - CP, CP = Cost Price
Loss Percentage \( \text{Loss \%} = \left( \frac{\text{Loss}}{CP} \right) \times 100 \) Loss = CP - SP, CP = Cost Price
Selling Price from Profit % \( SP = CP \times \left(1 + \frac{\text{Profit \%}}{100}\right) \) CP = Cost Price, Profit % = Profit Percentage
Selling Price from Loss % \( SP = CP \times \left(1 - \frac{\text{Loss \%}}{100}\right) \) CP = Cost Price, Loss % = Loss Percentage
Cost Price from SP and Profit % \( CP = \frac{SP}{1 + \frac{\text{Profit \%}}{100}} \) SP = Selling Price, Profit % = Profit Percentage
Cost Price from SP and Loss % \( CP = \frac{SP}{1 - \frac{\text{Loss \%}}{100}} \) SP = Selling Price, Loss % = Loss Percentage

Profit

Profit = SP - CP

Gain when selling price is more than cost price

SP = Selling Price
CP = Cost Price

Loss

Loss = CP - SP

Loss when selling price is less than cost price

CP = Cost Price
SP = Selling Price

Profit Percentage

\[Profit \% = \left( \frac{Profit}{CP} \right) \times 100\]

Profit as a percentage of cost price

Profit = SP - CP
CP = Cost Price

Loss Percentage

\[Loss \% = \left( \frac{Loss}{CP} \right) \times 100\]

Loss as a percentage of cost price

Loss = CP - SP
CP = Cost Price

Worked Examples

Example 1: Calculating Profit and Profit Percentage Easy
Given the cost price (CP) of an article is Rs.500 and the selling price (SP) is Rs.600, calculate the profit and profit percentage.

Step 1: Calculate the profit using the formula:

\( \text{Profit} = SP - CP = 600 - 500 = Rs.100 \)

Step 2: Calculate the profit percentage:

\( \text{Profit \%} = \left( \frac{100}{500} \right) \times 100 = 20\% \)

Answer: Profit is Rs.100 and profit percentage is 20%.

Example 2: Finding Selling Price Given Loss Percentage Medium
The cost price of an article is Rs.1200. If the seller incurs a loss of 10%, find the selling price.

Step 1: Use the formula for selling price when loss percentage is given:

\( SP = CP \times \left(1 - \frac{\text{Loss \%}}{100}\right) \)

Step 2: Substitute the values:

\( SP = 1200 \times \left(1 - \frac{10}{100}\right) = 1200 \times 0.9 = Rs.1080 \)

Answer: The selling price is Rs.1080.

Example 3: Successive Discounts and Profit Calculation Hard
An article is marked at Rs.2000. Two successive discounts of 10% and 5% are given. If the cost price is Rs.1600, find the profit or loss.

Step 1: Calculate the price after the first discount of 10%:

\( \text{Price after 1st discount} = 2000 \times (1 - 0.10) = 2000 \times 0.90 = Rs.1800 \)

Step 2: Calculate the price after the second discount of 5% on Rs.1800:

\( \text{Price after 2nd discount} = 1800 \times (1 - 0.05) = 1800 \times 0.95 = Rs.1710 \)

Step 3: This final price is the selling price (SP). Now calculate profit or loss:

\( \text{Profit} = SP - CP = 1710 - 1600 = Rs.110 \)

Step 4: Since profit is positive, calculate profit percentage:

\( \text{Profit \%} = \left( \frac{110}{1600} \right) \times 100 = 6.875\% \)

Answer: Profit is Rs.110, which is approximately 6.88%.

graph TD    A[Marked Price = Rs.2000] --> B[Apply 10% discount]    B --> C[Price = Rs.1800]    C --> D[Apply 5% discount]    D --> E[Final SP = Rs.1710]    E --> F[Compare with CP = Rs.1600]    F --> G[Profit = Rs.110]    G --> H[Profit % = 6.88%]  
Example 4: Determining Cost Price from Profit Percentage and Selling Price Medium
An article is sold for Rs.1320 at a profit of 10%. Find its cost price.

Step 1: Use the formula for cost price when selling price and profit percentage are given:

\( CP = \frac{SP}{1 + \frac{\text{Profit \%}}{100}} \)

Step 2: Substitute the values:

\( CP = \frac{1320}{1 + \frac{10}{100}} = \frac{1320}{1.10} = Rs.1200 \)

Answer: The cost price is Rs.1200.

Example 5: Calculating Profit Percentage from Cost Price and Selling Price Easy
Find the profit percentage if the cost price is Rs.800 and the selling price is Rs.880.

Step 1: Calculate the profit:

\( \text{Profit} = SP - CP = 880 - 800 = Rs.80 \)

Step 2: Calculate the profit percentage:

\( \text{Profit \%} = \left( \frac{80}{800} \right) \times 100 = 10\% \)

Answer: Profit percentage is 10%.

Tips & Tricks

Tip: Use the formula \( SP = CP \times (1 \pm \frac{\text{Profit or Loss \%}}{100}) \) to quickly find selling price without separately calculating profit or loss.

When to use: When cost price and profit or loss percentage are known, and you need to find selling price fast.

Tip: Always calculate profit and loss percentages based on cost price, never selling price.

When to use: To avoid confusion and errors during percentage calculations.

Tip: For successive discounts, multiply the complements of each discount. For example, for 10% and 5% discounts, multiply 0.9 x 0.95 = 0.855 to find the overall discount factor.

When to use: When solving problems with multiple successive discounts.

Tip: Convert percentages to decimals before multiplying to simplify calculations.

When to use: During mental math or quick calculations.

Tip: If profit or loss percentage is small, approximate calculations by ignoring higher-order terms for faster estimation.

When to use: In time-limited exams requiring quick answers.

Common Mistakes to Avoid

❌ Calculating profit or loss percentage based on selling price instead of cost price.
✓ Always calculate profit or loss percentage using cost price as the base.
Why: Profit and loss percentages are defined relative to cost price, not selling price.
❌ Confusing profit with loss and using incorrect formulas interchangeably.
✓ Check whether SP > CP (profit) or SP < CP (loss) before applying formulas.
Why: Misapplication leads to negative or incorrect results.
❌ Ignoring units or currency leading to inconsistent answers.
✓ Always include and maintain consistent units (Rs. and metric) throughout calculations.
Why: Units ensure clarity and correctness in real-world problems.
❌ Incorrectly applying successive discounts by adding percentages instead of multiplying complements.
✓ Use multiplication of (1 - discount fraction) for each successive discount.
Why: Adding percentages overestimates the total discount.
❌ Rounding off intermediate values too early causing inaccurate final answers.
✓ Perform calculations with full precision and round off only the final answer.
Why: Early rounding accumulates errors.
Curated videos per subtopic
Top YouTube explainers, AI-ranked for your exam and language. Unlocks with subscription.
Unlock

Try Practice next.

Progress tracking is paywalled — subscribe to mark subtopics as understood and save your streak.

Go to practice →
Ask a doubt
Profit and Loss · 10 free messages
Ask me anything about this subtopic. You have 10 free messages this session — chat history isn't saved in preview.