Mathematics · Class 4
The Junk Seller
Learn The Junk Seller with notes, examples, and practice questions.
3 sections15–25 min read3 MCQs · 1 examples
Chapter Overview
100 paise = ₹1. Profit = selling price − cost price when the selling price is greater.
The Junk Seller builds money sense through buying and selling recyclable materials. Learners calculate costs, bills, change, and simple profit or loss using rupees, paise, multiplication, and subtraction.
Bills and Change
- Cost of several equal items = price of one × quantity.
- Add all item costs to find a bill total.
- Change = amount paid − bill total.
- Align rupees and paise carefully when adding money.
Buying and Selling
- Cost price is what a seller pays for an item.
- Selling price is what the customer pays.
- A higher selling price gives profit; a lower one gives loss.
- Compare prices for the same quantity or weight.
Solved Examples
Step-by-step solutions — read each step before checking the final answer.
Calculate Earnings
A junk seller buys 8 kg of paper at ₹6 per kg and sells it for ₹9 per kg. What profit is made?
- 1Cost price = 8 × ₹6 = ₹48.
- 2Selling price = 8 × ₹9 = ₹72.
- 3Profit = ₹72 − ₹48 = ₹24.
Answer
₹24 profit
Key Points to Remember
- ✓ Multiply rate by quantity
- ✓ Subtract total from payment for change
- ✓ Distinguish cost price from selling price
- ✓ Profit and loss compare buying and selling amounts
Exam Tips
- • Use the ₹ symbol correctly
- • Check whether a rate is per kilogram or total
- • Calculate cost and selling totals before finding profit
Practice MCQs — The Junk Seller
Test your understanding with topic-wise multiple choice questions. Explanations appear after each answer.
Question 1 of 3Score: 0/0
What is the cost of 7 kg of metal at ₹12 per kg?