Addition with Regrouping

🎯 What Will We Learn Today?

What happens when two digits add up to more than 9? That's when we need regrouping（also called "carrying"）! Today we'll master this essential addition skill.

📚 What Is Regrouping?

Regrouping happens when the sum in one column is 10 or more. We "carry" the extra to the next column:

`
¹
27
+ 15
---
42
`

7 + 5 = 12 → write 2, carry 1 to the tens column → 1 + 2 + 1 = 4

🎮 Step-by-Step Regrouping

Example 1: 38 + 26

Step 1 — Ones column: 8 + 6 = 14
Write 4 in the ones place, carry 1 to the tens place.

Step 2 — Tens column: 1（carried）+ 3 + 2 = 6
Write 6 in the tens place.

Answer: 64

Example 2: 156 + 178

Ones: 6 + 8 = 14 → write 4, carry 1
Tens: 1 + 5 + 7 = 13 → write 3, carry 1
Hundreds: 1 + 1 + 1 = 3 → write 3

Answer: 334

💡 Tips for Success

Always start from the right（ones column）

Write the carried number above the next column

Double-check: does each column's sum make sense?

📝 Practice Problems

45 + 27 = ?

68 + 19 = ?

234 + 189 = ?

You have 156 stickers and your friend gives you 178 more. How many do you have now?

Explain why we "carry" when a column adds up to 10 or more.

🎮 Play a Game!

Practice addition with Jet Ski Addition!