How to Add and Subtract Decimals (Step-by-Step Examples) | Math with Mr. J
From Math with Mr. J
30 min5thMath
Summary
How to add and subtract decimals by lining up the decimal points and adding place by place. Mr. J shows how to fill in with zeros.
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All ages
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Teaching resources
Discussion questions
Line up the decimal points so you add tenths to tenths and hundredths to hundredths.
- Why do you line up the decimal points?
- How can adding a zero help you subtract decimals?
- Where does the decimal point go in your answer?
Quick work-a-long
Words to know: decimal point, line up, place value
- Solve 4.5 + 3.27.
- Solve 6.4 - 2.85.