By Diego Marinho 道 Soroban Dojo Small steps, steady hands · そろばん道場
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Lesson · L2

Complements to Ten

complements 18 min child, adult 数 一零
All lessons This level Worksheet
L2Level
complementsSkill
18mTime
child/adultAudience
Complements to FivePrerequisite
Best for

Best for strengthening number balance and cleaner movement on the soroban.

1. Read the core idea 2. Study the worked example 3. Practice the related drills

Core idea

Learn the pairs that complete ten so larger transitions feel cleaner.

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Objectives

  • Recognize pairs that make ten.
  • Prepare for smoother multi-step addition and subtraction.

Reusable visual engine

Worked visual for Complements to Ten

Value 10 · 一零

Step 1

10

Step 2

7

Complements to ten matter when a digit needs help from the next place or from a cleaner mental pattern.

Pairs to remember

  • 1 and 9
  • 2 and 8
  • 3 and 7
  • 4 and 6
  • 5 and 5

Step by step for adding 3 to 7

  1. Start from 7.
  2. Notice that 7 needs 3 more to reach 10.
  3. Complete the ten.
  4. Re-read the value before continuing.

Next step

Continue with guided practice

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Previous lesson

Complements to Five

Use number pairs to move more efficiently on the soroban.

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