Mentally Add and Subtract Numbers Ending in Zeroes

Master the superpower of quick calculations with numbers ending in zero!

The Magic of Zero-Ending Numbers

Did you know numbers ending in zeroes are some of the easiest to work with?
When we add or subtract numbers that end with zeroes, we can use a special trick to make calculations faster and easier. This is called "mental math" because we can do it in our heads without writing anything down!

How to Add/Subtract Numbers Ending in Zeroes

1️⃣ Ignore the zeroes at first and just look at the numbers before them

2️⃣ Add or subtract these numbers normally

3️⃣ Put the zeroes back at the end of your answer

Let's Try Some Examples!

Example 1: Addition

What is 300 + 500?

Step 1: Ignore the zeroes: 3 + 5 = 8

Step 2: Count the zeroes (there are 2 in each number)

Step 3: Add 2 zeroes to your answer: 800

👉 Click to reveal answer

Example 2: Subtraction

What is 70 - 20?

Step 1: Ignore the zeroes: 7 - 2 = 5

Step 2: Count the zeroes (there is 1 in each number)

Step 3: Add 1 zero to your answer: 50

👉 Click to reveal answer

3 00 + 5 00 = 8 00

Parent Tips 🌟

  • Make it a game: Challenge your child to calculate prices at the store (e.g., $300 toy + $200 game = ?)
  • Use real-life examples: "If we drive 400 miles today and 300 miles tomorrow, how far will we go?"
  • Practice with different zero counts: Start with numbers ending in one zero (10, 20), then two (100, 200), etc.

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