🔓

Breaking a Ten!

Chapter 7: Subtraction With Borrowing

Sometimes we don't have enough ones to subtract. What do we do? We open a bundle of ten! One ten becomes ten ones — we're not taking extra, just rearranging what we have.

❓

Check First

🔓

Break a Ten

➖

Subtract

✅

Check Work

👧🏽

🐕

Not Enough Stickers!

Riya wants to give away some stickers. 🌟

"I have 42 stickers. I want to give 18 stickers."

Milo looks worried. "Wait! You only have 2 loose ones. You need to give 8!"

Riya smiles. "I'll open a bundle! One ten becomes ten ones."

🧠

Recall: Safe Subtraction

When we have enough ones

First, let's remember when subtraction is easy — when we have enough ones!

Start

47

−

Take away

23

=

Left

24

Do we have enough ones?

✓ Yes! 7 ≥ 3

💡 The key question: "Do I have enough ones?" When the answer is YES, we don't need to borrow!

⚠️

When Ones Are Not Enough

The problem moment

Let's try: 42 − 18

I have

42

4 tens + 2 ones

−

Need to take

18

1 tens + 8 ones

😟

Problem! I have 2 ones, but I need to take away 8 ones!

Ones: 2 ≥ 8?

✗ NO!

⚠️ We can't just subtract! 2 − 8 doesn't work. We need help from the tens place.

🔓

Breaking a Ten

The borrow moment — watch carefully!

We don't take extra — we reorganise what we already have.

One Ten Becomes Ten Ones

Before: 4 tens, 2 ones

42 total

➡️

After: 3 tens, 12 ones

Still 42!

💡

"We don't take extra. We rearrange what we have."

🔓 Key insight: 4 tens + 2 ones = 3 tens + 12 ones. Same total, different arrangement!

✨

Complete Subtraction

Step by step with borrowing

42 − 18 = ?

Start with

42

4 tens + 2 ones

−

Take away

18

=

Left

?

Step 1: Check — do we have enough ones?

📝

Writing It Down

Vertical subtraction with borrowing

When we write borrowing, we show: cross out the old, write the new

T

O

3

12

−

1

8

2

4

⚠️

"We borrow a TEN, not a one!"

💡 Check: Ones: 12 − 8 = 4 ✓ | Tens: 3 − 1 = 2 ✓ | Answer: 24

🔧

Fix Milo's Mistakes!

Learn by spotting errors

🐕

"I did 52 − 27. I borrowed a ten, so now I have 4 tens and 12 ones. Then 12 − 7 = 5 ones, and 4 − 2 = 2 tens. My answer is 25!"

52 − 27 = 25

Milo's work: 4 tens + 12 ones → 12−7=5, 4−2=2

What's wrong with Milo's work?

Nothing — it's correct!

He forgot to reduce the tens after borrowing

He subtracted wrong in the ones

🎯

Practice Zone

Build your borrowing skills!

0

CORRECT

0

TOTAL

0

🔥 STREAK

NEEDS BORROWING

52 − 27 = ?

📝

Chapter Quiz

10 questions to earn your certificate!

1/10

🏆

0/10

Great job!

⭐⭐⭐

🎓 Certificate of Achievement 🎓

🔓

This certifies that

Math Explorer

has successfully completed

Chapter 7: Subtraction With Borrowing

Breaking a Ten

🌍

Borrowing in Real Life

Rearranging resources

💰

Breaking a ₹10 Note

"I have ₹32 but need to pay ₹15. I break a ₹10 into coins to give exact change."

🍪

Opening a Cookie Pack

"I have 2 packs of 10 and 3 loose. To share 7, I open one pack!"

📚

Sharing Books

"Class has 41 books. 16 go to another class. Open a bundle to count!"

🎨

Crayons in Boxes

"Have 53 crayons in boxes of 10. Give 28 away — need to open a box!"

💡 The real world: Whenever you "break" something big into smaller parts to share — that's borrowing in action!

👨‍👩‍👧 Parent / Teacher Corner

▼

CBSE Class 2 Mathematics

Chapter Reference

NCERT Math-Magic: Subtraction with Borrowing/Regrouping

Learning Outcomes

✓ Recognise when borrowing is needed

✓ Regroup one ten as ten ones

✓ Subtract two-digit numbers with borrowing

✓ Verify total remains unchanged after regrouping

Cambridge Primary Stage 2

Framework Reference

Number N6–N7: Use regrouping strategies for subtraction

Learning Outcomes

✓ Exchange one ten for ten ones

✓ Subtract with regrouping using place value

✓ Explain regrouping with manipulatives

ICSE Class 2 Mathematics

Syllabus Reference

Subtraction of two-digit numbers with borrowing

Learning Outcomes

✓ Subtract with borrowing from tens place

✓ Write subtraction showing regrouping

✓ Solve word problems requiring borrowing

⚠️ Language Matters

Avoid: "Borrow one from the tens" — This implies taking something extra.

Use: "Break a ten" or "Open a bundle" — This shows rearrangement.

Key phrase: "We borrow a TEN, not a one." Many children think they're borrowing "1" when they're actually taking 10.

⚠️ Common Mistakes

Forgetting to reduce tens: Child borrows but doesn't subtract 1 from tens digit.

Subtracting smaller from larger: Writing 2 − 8 = 6 instead of recognizing borrowing is needed.

Borrowing unnecessarily: Borrowing even when ones digit is sufficient.

Adding instead of making 12: Writing 10 + 2 = 12 but forgetting to use 12 in subtraction.

🏠 Home Activities

Money exchange: Use real coins. Break a ₹10 note into ten ₹1 coins to demonstrate.

Bundle breaking: Make bundles of 10 straws. Practice opening them to subtract.

Before/after: Count total before borrowing, count after. Same number!

💜 Signs of readiness: Child confidently asks "Do I have enough ones?" before starting. Child understands 1 ten = 10 ones. Child can explain why the total stays the same after regrouping.