Subtracting Tens
Aligned to 1.NBT.C.6 — Common Core State Standards for Mathematics.
What this lesson teaches
When we subtract tens from tens, we just count how many tens are left.
Worked example
50 - 20. That is 5 tens take away 2 tens, which leaves 3 tens. So 50 - 20 = 30.
Practice questions
- Subtract 40 - 10.
- Subtract 70 - 30.
- Subtract 90 - 50.
Watch the lesson
Every lesson comes with a video taught in English and Spanish — the same video the QR code in the printed workbook opens.
▶ Watch this lessonEn español
Restar decenas
Cuando restamos decenas de decenas, solo contamos cuántas decenas quedan.
Ejemplo: 50 - 20. Eso es 5 decenas menos 2 decenas, y quedan 3 decenas. Así que 50 - 20 = 30.
More Number & Operations in Base Ten lessons
Tens and Ones (Place Value)1.NBT.B.2Counting to 1201.NBT.A.1Which Is Bigger?1.NBT.B.3Adding Bigger Numbers1.NBT.C.410 More, 10 Less1.NBT.C.5
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