Subtract by Thinking Addition
Aligned to 1.OA.B.4 — Common Core State Standards for Mathematics.
What this lesson teaches
To subtract, we can ask what number we add to reach the bigger number.
Worked example
10 - 8 = ? Think: 8 plus what makes 10? 8 + 2 = 10, so 10 - 8 = 2.
Practice questions
- Solve 9 - 6 by thinking 6 plus what makes 9.
- Solve 7 - 4.
- 8 plus what makes 10? So 10 - 8 = ?
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 pensando en sumar
Para restar, podemos preguntar qué número le sumamos para llegar al número más grande.
Ejemplo: 10 - 8 = ? Piensa: ¿8 más cuánto hace 10? 8 + 2 = 10, así que 10 - 8 = 2.
More Operations & Algebraic Thinking lessons
Adding and Subtracting within 201.OA.C.6Story Problems1.OA.A.1Adding Three Numbers1.OA.A.2Add in Any Order1.OA.B.3Counting On1.OA.C.5Is It True or False?1.OA.D.7
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