CurriculumGrade 1Mathematics

Adding Three Numbers

Aligned to 1.OA.A.2 — Common Core State Standards for Mathematics.

What this lesson teaches

To add three numbers, we add two of them first, then add the last one to that answer.

Worked example

2 + 3 + 4. First add 2 + 3 = 5. Then add 5 + 4 = 9.

Practice questions

  1. Add 1 + 2 + 3.
  2. Add 5 + 5 + 2.
  3. Add 4 + 6 + 4.

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.

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En español

Sumar tres números

Para sumar tres números, sumamos dos de ellos primero y luego le sumamos el último a esa respuesta.

Ejemplo: 2 + 3 + 4. Primero suma 2 + 3 = 5. Luego suma 5 + 4 = 9.

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