CCSS.Math.Content.5.NF.A.2
The Standard
Solve word problems involving addition and subtraction of fractions referring to the same whole, including cases of unlike denominators, e.g., by using visual fraction models or equations to represent the problem. Use benchmark fractions and number sense of fractions to estimate mentally and assess the reasonableness of answers.
Common Core State Standards for Mathematics · Number and Operations—Fractions
Teacher's field guide
What This Standard Means
What Students Need to Do
- Students decide whether a fraction story calls for addition or subtraction. They use diagrams or equations to find an exact answer with unlike denominators. They estimate with benchmark fractions to check whether the result makes sense.
What Mastery Looks Like
- Students represent the situation with a diagram or equation and choose the correct operation. They find a common denominator and calculate accurately. They use benchmarks such as 0, 1/2, and 1 to explain why the answer is reasonable.
Common Misconceptions
- Students may add or subtract both numerators and denominators. They may choose an operation from keywords without making sense of the situation. Some forget that the fractions must refer to the same-sized whole.
How to Assess It
- Exit ticket: “Maya walked 2/3 mile before lunch and 3/4 mile after lunch. Write an equation, solve, and use a benchmark to check your answer.”
Lesson moves
Ways to Teach It
Give pairs fraction strips to model 2/3 + 3/4, rename both fractions, and record a matching equation.
Ask, “Why can’t 2/5 + 1/2 equal 3/7?” Students write a benchmark-based explanation and compare responses.
Play Fraction Estimate Match: students pair problem cards with benchmark estimates, then solve to confirm each match.
Use a recipe card: combine 3/4 cup oats and 2/3 cup nuts, then decide whether the total exceeds 1 cup.
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Printable 5.NF.A.2 Worksheet
A ready-to-print activity worksheet aligned to CCSS.Math.Content.5.NF.A.2, with an answer key for the teacher on its own page. No account needed.
PDF, US Letter, prints cleanly in black and white.
Download the worksheetLearning progression
Where This Standard Sits
See the whole path on the Number & Operations: Fractions progression map.
Before This Standard
If students are struggling here, check these first.
- CCSS.Math.Content.4.NF.A.1
Generating equivalent fractions is needed to rename unlike denominators before adding or subtracting fractions in word problems.
- CCSS.Math.Content.5.NF.A.1
Students must find common denominators and add or subtract fractions before solving and checking fraction word problems accurately.
- CCSS.Math.Content.4.NF.B.3d
Like-denominator fraction word problems carry over the same whole, models, equations, and reasonableness checks before adding unlike denominators.
What This Unlocks
Mastery here sets students up for these next.
Keep exploring
Related Standards
- CCSS.Math.Content.6.NS.A.1
Interpret and compute quotients of fractions, and solve word problems involving division of fractions by fractions, e.g., by using visual fraction models and eq...
- CCSS.Math.Content.4.NF.B.4c
Solve word problems involving multiplication of a fraction by a whole number, e.g., by using visual fraction models and equations to represent the problem.
- CCSS.Math.Content.5.NF.B.6
Solve real world problems involving multiplication of fractions and mixed numbers, e.g., by using visual fraction models or equations to represent the problem.
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