Adding Several Two-Digit Numbers
Aligned to 2.NBT.B.6 — Common Core State Standards for Mathematics.
What this lesson teaches
To add three or four numbers, add the tens together and the ones together, then put the parts back together.
Worked example
12 + 23 + 14: add tens 10+20+10 = 40; add ones 2+3+4 = 9; then 40 + 9 = 49.
Practice questions
- Add 21 + 32 + 15.
- Add 10 + 20 + 30 + 25.
- Add 14 + 14 + 14.
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
Sumar varios números de dos dígitos
Para sumar tres o cuatro números, suma las decenas juntas y las unidades juntas, y luego une las partes.
Ejemplo: 12 + 23 + 14: suma las decenas 10+20+10 = 40; suma las unidades 2+3+4 = 9; luego 40 + 9 = 49.
More Number & Operations in Base Ten lessons
Adding and Subtracting within 1002.NBT.B.5Hundreds, Tens, and Ones2.NBT.A.1Counting and Skip-Counting2.NBT.A.2Reading and Writing Numbers to 10002.NBT.A.3Comparing Three-Digit Numbers2.NBT.A.4Adding and Subtracting within 10002.NBT.B.7
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