Learning to subtract 3-digit numbers with borrowing tens for Grade 2

📚 What is Subtracting 3-Digit Numbers with Borrowing (from Tens)?

Subtracting 3-digit numbers with borrowing from the tens place involves taking away one number from another when the digit in the ones place of the number being subtracted is larger than the digit in the ones place of the number you are subtracting from. This requires 'borrowing' a ten from the tens place to make the subtraction possible.

📜 A Little History of Subtraction

The concept of subtraction has been around for thousands of years. Ancient civilizations like the Egyptians and Babylonians used subtraction to solve problems related to trade, agriculture, and construction. The symbols and methods we use today have evolved over time, making subtraction easier to understand and apply.

🔑 Key Principles of 3-Digit Subtraction with Borrowing

• 🔢 Place Value: Understand hundreds, tens, and ones. Knowing what each digit represents is crucial.
• 🤝 Borrowing: When the top digit in the ones place is smaller than the bottom, borrow 10 from the tens place.
• ➖ Subtraction Process: Subtract column by column, starting from the ones place.
• ✅ Verification: Check your answer by adding the result to the number you subtracted; it should equal the original number.

➕ Real-World Examples

Let's explore some practical examples to illustrate 3-digit subtraction with borrowing:

Example 1: Library Books

Sarah has 432 books in her personal library. She donates 118 books to the local school. How many books does Sarah have left?

Here's how to solve it:

1. Set up the subtraction problem: $432 - 118$
2. Start with the ones place: Since 2 is less than 8, we need to borrow.
3. Borrow 1 ten from the tens place (3 becomes 2), and add it to the ones place (2 becomes 12).
4. Subtract the ones: $12 - 8 = 4$
5. Subtract the tens: $2 - 1 = 1$
6. Subtract the hundreds: $4 - 1 = 3$

Sarah has 314 books left.

Example 2: School Supplies

A school has 654 pencils. They give out 237 pencils to students. How many pencils are left?

Here's how to solve it:

1. Set up the subtraction problem: $654 - 237$
2. Start with the ones place: Since 4 is less than 7, we need to borrow.
3. Borrow 1 ten from the tens place (5 becomes 4), and add it to the ones place (4 becomes 14).
4. Subtract the ones: $14 - 7 = 7$
5. Subtract the tens: $4 - 3 = 1$
6. Subtract the hundreds: $6 - 2 = 4$

There are 417 pencils left.

📝 Practice Quiz

Solve these subtraction problems with borrowing:

1. $321 - 115 = ?$
2. $543 - 226 = ?$
3. $762 - 348 = ?$
4. $984 - 567 = ?$
5. $450 - 132 = ?$
6. $671 - 453 = ?$
7. $895 - 279 = ?$

💡 Tips and Tricks

• 🎨 Use Visual Aids: Draw circles or lines to represent numbers and help with borrowing.
• 🧱 Base Ten Blocks: Using physical blocks can make the concept of borrowing more concrete.
• 🗣️ Verbalize the Process: Talk through each step as you solve the problem.
• ➕ Check Your Work: Add the difference to the number you subtracted to ensure it equals the original number.

🏁 Conclusion

Mastering 3-digit subtraction with borrowing from the tens place is a fundamental skill in mathematics. By understanding the principles, practicing regularly, and using helpful tips, you can become proficient in subtraction. Keep practicing, and you'll become a subtraction superstar! ⭐