The Break-Ten Trick: 13 − 9
⏱ 0:27📘 Grade 1 · Subtracting within 20
3 is too small to take away 9, so open the bundle of ten: 10 − 9 = 1, then 1 + 3 = 4. So 13 − 9 = 4.
The videos are narrated in Mandarin Chinese with on-screen subtitles.
📚 What you will learn
- 13 is one ten and 3 ones: a bundle of 10 sticks and 3 loose sticks.
- 3 is too small to take away 9, so break the ten.
- Take 9 from the ten: 10 − 9 = 1.
- Put what is left together: 1 + 3 = 4. So 13 − 9 = 4.
- Break-ten steps: split off the ten, subtract from it, then add the leftovers.
🎙️ What the video says (in Chinese)
- 13 − 9：3 减 9 不够减，怎么办？用破十法！
- 13 根小棒，就是一捆 10 根和 3 根。
- 3 根不够减，就打开这一捆，从 10 根里拿走 9 根。
- 10 − 9 = 1，还剩 1 根。
- 1 根和 3 根合起来是 4 根，所以 13 − 9 = 4！
- 破开十，先减，再把剩下的加起来！
✏️ Try it yourself
Use break-ten: 15 − 9 = ?
Show answer
10 − 9 = 1, 1 + 5 = 6
12 − 8 = ?
Show answer
10 − 8 = 2, 2 + 2 = 4
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