Worked Example 1
Adding Decimals
4.56 + 2.375
- 1Line up the decimal points: 4.560 + 2.375.
- 2Add each column from right to left, regrouping as needed.
- 34.560 + 2.375 = 6.935.
Answer: 6.935
Florida Grade 5 Math · Number Sense and Operations
MA.5.NSO.2.3: Adding and subtracting decimals
What this Grade 5 benchmark means, worked examples, common mistakes, and a free printable worksheet.
Created by a Florida mom · Published by Tropical Learning LLC
What Is Benchmark MA.5.NSO.2.3?
In Grade 5, students add and subtract decimals to the thousandths, such as 4.56 + 2.375 or 7 − 2.48, including with the standard algorithm.
The key idea: line up the decimal points so each place is added to the same place. Writing extra zeros at the end keeps the columns even.
Official benchmarkAdd and subtract multi-digit numbers with decimals to the thousandths, including using a standard algorithm with procedural fluency.
On the FAST test: part of the Grade 5 reporting category Number Sense and Operations with Fractions and Decimals, which is about 23–29% of the test.
Worked Examples
Worked Example 2
Subtracting from a Whole Number
7 − 2.48
- 1Write 7 as 7.00.
- 27.00 − 2.48: regroup to subtract the hundredths and tenths.
- 37.00 − 2.48 = 4.52.
Answer: 4.52
Common Mistakes to Watch For
Lining up the last digits instead of the decimal points
Wrong:3.42 + 1.9 = 3.61
Line up the decimal points: 3.42 + 1.90 = 5.32.
Not regrouping when subtracting from zeros
Wrong:7 − 2.48 = 5.48
Write 7 as 7.00 and regroup: 7.00 − 2.48 = 4.52.
Helpful Math Tip
Estimate with whole numbers first. 3.42 + 1.9 is about 3 + 2 = 5, so 3.61 cannot be right.
Related Grade 5 Skills
Make Florida Math Practice More Fun
Help your child build math confidence with original interactive questions aligned with Florida's B.E.S.T. Mathematics Standards.
Start Practicing FreeIndependent Educational Platform. FastChomp is published by Tropical Learning LLC and is not affiliated with, sponsored by, or endorsed by the Florida Department of Education. FAST and Star assessment names are referenced for informational purposes only. FastChomp practice questions are original educational materials, not official Florida FAST assessment questions.