Grade 5 Add & Subtract Decimals

Add & Subtract Decimals: Line Up the Points

Steps

Estimate first: round to whole numbers. 3.6 + 2.45 ≈ 4 + 2 = 6.
Line up the decimal points: tenths under tenths, hundredths under hundredths.
Placeholder zeros fill empty places: 3.6 = 3.60, 5 = 5.00.
Add or subtract from the right and regroup when needed. Bring the point straight down: 3.60 + 2.45 = 6.05.
Check: is it close to the estimate? Use the inverse: 5 − 1.38 = 3.62, so 3.62 + 1.38 = 5 ✓
Rhyme: “Estimate first, then line up each point. Zeros fill the gaps, regroup, and check every joint!”