Mastering Mental Addition Techniques for 3-Digit Numbers

The video tutorial introduces techniques for performing mental addition by simplifying numbers. It demonstrates how to adjust numbers to make calculations easier, using examples like 355 + 480, 18 + 704, and 275 + 595. The tutorial emphasizes breaking numbers into simpler parts and rearranging them to facilitate mental computation, providing a toolkit for solving addition problems without paper.

What is the first step in simplifying the addition of 355 and 480?

• Subtract 20 from 355

• Divide 480 by 2

• Multiply 355 by 2

• Add 20 to 480

What is the result of 335 plus 500?

• 850

• 730

• 835

• 800

Tags

CCSS.2.NBT.B.7

CCSS.3.NBT.A.2

How can 18 be adjusted to simplify adding it to 704?

• Subtract 6 from 18

• Add 4 to 18

• Subtract 4 from 18

• Add 6 to 18

Tags

CCSS.2.NBT.B.7

What is the sum of 22 and 700?

• 715

• 720

• 730

• 722

Tags

CCSS.2.NBT.B.7

CCSS.3.NBT.A.2

Which of the following is a correct adjustment for easier addition of 704?

• Decreasing it to 700

• Increasing it to 710

• Decreasing it to 690

• Increasing it to 720

What is the simplified form of 595 to make addition easier?

• 600

• 580

• 590

• 610

Tags

CCSS.1.NBT.C.5

What is the result of adding 270 and 600?

• 850

• 870

• 860

• 880

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CCSS.3.NBT.A.2

CCSS.2.NBT.B.7

What alternative method is suggested for simplifying 275 for addition?

• Adjusting it to 320

• Adjusting it to 250

• Adjusting it to 280

• Adjusting it to 300

What is the final result of adding 300 and 570?

• 870

• 860

• 850

• 880

Tags

CCSS.3.NBT.A.2

CCSS.2.NBT.B.7

What is the purpose of adjusting numbers before adding them mentally?

• To learn division

• To practice subtraction

• To make the numbers larger

• To simplify the calculation

Tags

CCSS.1.OA.A.1