Add and subtract numbers up to 100

key notes :

🔢 Understanding Numbers up to 100

• Numbers up to 100 have tens and ones.
  👉 Example: 45 = 4 tens + 5 ones
• Use a number chart (1–100) to find and understand numbers.

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➕ Addition up to 100

Addition means putting together or finding the total.

Add ones first, then tens.

Write numbers in columns (tens under tens, ones under ones).

You can use:

• Number line
• Base-ten blocks
• Fingers or objects

👉 Example:
34 + 25 = (30 + 20) + (4 + 5) = 50 + 9 = 59

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➖ Subtraction up to 100

Subtraction means taking away or finding the difference.

Subtract ones first, then tens.

Use:

• Number line (jump backward)
• Objects or blocks

👉 Example:
56 − 23 = (50 − 20) + (6 − 3) = 30 + 3 = 33

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🔄 Regrouping (Carrying & Borrowing)

Sometimes we need to regroup:

• Addition: Carry to tens when ones are more than 9
• Subtraction: Borrow from tens when ones are smaller

👉 Example (Addition):
28 + 17 = 45

👉 Example (Subtraction):
52 − 38 = 14

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🎯 Important Tips

Always line up tens and ones correctly.

Start from the ones place.

Check your answer using the opposite operation:

• Addition ↔ Subtraction

Practice using real-life examples (money, objects, etc.).

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🎉 Fun Practice Ideas

• Use coins or sticks to add and subtract.
• Play number games using a 100 chart.
• Solve simple word problems.

Learn with an example

Let’s practice!🖊️