Rounding Decimals
Aligned to 5.NBT.A.4 — Common Core State Standards for Mathematics.
What this lesson teaches
To round a decimal, look at the digit just to the right of the place you want. If it is 5 or more, round up; if it is 4 or less, keep the digit the same. Then drop the digits after your rounding place.
Worked example
Round 3.147 to the nearest hundredth. The hundredths digit is 4, and the digit right after it (the thousandths) is 7. Since 7 is 5 or more, round the 4 up to 5. So 3.147 rounds to 3.15.
Practice questions
- Round 5.62 to the nearest tenth.
- Round 0.238 to the nearest hundredth.
- Round 12.495 to the nearest hundredth, and explain the digit you checked.
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
Redondear decimales
Para redondear un decimal, mira el dígito que está justo a la derecha del lugar que quieres. Si es 5 o más, redondea hacia arriba; si es 4 o menos, deja el dígito igual. Luego quita los dígitos que siguen después de tu lugar de redondeo.
Ejemplo: Redondea 3.147 a la centésima más cercana. El dígito de las centésimas es 4, y el dígito que le sigue (las milésimas) es 7. Como 7 es 5 o más, redondea el 4 hacia arriba a 5. Así, 3.147 se redondea a 3.15.
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