The Junk Seller Chapter Notes | Mathematics for Class 4: NCERT PDF Download

Junk Seller

• A person who buys and sells used or discarded items is known as a junk seller.

• Junk is debris, waste, or garbage that has been left behind or discarded because it is unwanted.

What is Currency

Currency is a special type of money that is used in a country.Currency is important because it helps us buy things we need or want. Imagine if we had to trade goods directly instead of using money. For example, if you wanted to buy a toy, you might have to give something else in exchange, like a book or a snack .

Currency in India

 In India, currency consists of coins and notes that are issued by the Reserve Bank of India, which is like the country's bank. These coins and notes have different values, such as 1 rupee, 2 rupees, 5 rupees, 10 rupees, and so on. They are used by people to buy things like food, clothes, toys, and other items. Currency helps us trade goods and services with each other and makes it easier for us to buy and sell things.

• Banknotes in India are now printed in denominations of 10, 20, 50, 100, 200, 500, and 2000 rupees. 

• As they are issued by the RBI, these notes are known as banknotes.

Let's See How Money Works 

• Sure! Imagine you have some chocolates, and you want to share them equally with your friends. Let's say you have 20 chocolates, and you want to share them with 5 friends. To find out how many chocolates each friend will get, you can use the unitary method.
• First, you divide the total number of chocolates (20) by the total number of friends (5). So, 20 chocolates ÷ 5 friends = 4 chocolates.
• This means that each friend will get 4 chocolates. So, using the unitary method, you can find out how many chocolates each friend gets when you divide the total number of chocolates by the total number of friends.

Example:

Ex 1.  If 1 Toblerone cost 100 Rs then what would be the cost of 5 Toblerone ?

Ans: 5 Toblerone would cost 5 x cost of one Toblerone = 5 x 100 = 500

Ex 2. If a car travels 60 km in 2 hours, how far can it travel in 6 hours?

Ans: If a car travels 60 km in 2 hours, then it travels 60 km / 2 hours = 30 km per hour. Therefore, in 6 hours, it would travel 30 km/hour * 6 hours = 180 km.

Let's Practice with some more  Examples

Ex1. Find Prize of 5 Watches ?

Ans:   3 watch = 1200 so one will cost 400 so the prize of 5 watches would be 5x400 = 2000

Ex2. If 5 Books weight 5Kg, how much would 3 Books would Weight?

Ans : 5 Books weight 5Kg . Then 1 would weight 1 kg . Therefore, the cost of 3 books would be 3 kg

Ex3. If a book has 200 pages and you read 20 pages every day, how many days will it take you to finish the book?

Ans : If a book has 200 pages and you read 20 pages every day, then you would finish the book in 200 pages / 20 pages/day = 10 days.