CurriculumGrade 6Mathematics

Operating with Decimals

Aligned to 6.NS.B.3 — Common Core State Standards for Mathematics.

What this lesson teaches

To add or subtract decimals, line up the decimal points. To multiply, ignore the points, multiply, then count decimal places. To divide, shift the point in both numbers so you are dividing by a whole number.

Worked example

7.2 ÷ 0.9: move each point one place → 72 ÷ 9 = 8. Check by multiplying: 8 × 0.9 = 7.2. ✓

Practice questions

  1. Add 14.65 + 8.9.
  2. Multiply 3.4 × 2.5.
  3. A ribbon is 12.6 meters long and is cut into pieces 0.7 meters each. How many pieces?

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

Operaciones con Decimales

Para sumar o restar decimales, alinea los puntos decimales. Para multiplicar, ignora los puntos, multiplica y luego cuenta los lugares decimales. Para dividir, mueve el punto en ambos números para dividir entre un número entero.

Ejemplo: 7.2 ÷ 0.9: mueve cada punto un lugar → 72 ÷ 9 = 8. Comprueba multiplicando: 8 × 0.9 = 7.2. ✓

More The Number System lessons

Dividing Fractions6.NS.A.1Multi-Digit Decimals, GCF/LCM, and Negative Numbers6.NS.C.6Long Division with Big Numbers6.NS.B.2GCF, LCM, and Factoring Sums6.NS.B.4Positive and Negative Numbers6.NS.C.5Ordering and Absolute Value6.NS.C.7

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