Grade 5 · Fractions · MAT-05-NF-013
Solve Fraction Multiplication Word Problems
Represent and solve solve fraction multiplication word problems problems using accurate mathematical models, notation, and reasoning.
Learning objectives
What you should be able to do
- Represent and solve solve fraction multiplication word problems problems using accurate mathematical models, notation, and reasoning.
- Explain why a strategy for solve fraction multiplication word problems works and verify the result with an independent check.
Prerequisite check
Make sure the foundation is ready.
The new lesson builds directly on this prior concept, so the prerequisite should be usable rather than merely familiar.
Learn
Build the idea from meaning, not memorization.
Meaning and structure
Solve Fraction Multiplication Word Problems depends on treating fractions as numbers built from equal-sized units. The numerator counts those units and the denominator defines their size; operations are valid only when the units being combined are compatible.
Represent the idea
The Math Box uses fraction model as the primary representation. Translate the situation into numbers or geometry first, identify what stays fixed, then change one quantity at a time and observe which relationships remain invariant.
Reason, calculate, and verify
A convincing solution names the quantities, shows the mathematical relationship, computes accurately, and includes a reasonableness check rather than relying on an unsupported answer.
Math Box · Interactive lesson
Touch the math. Change it. See what stays true.
Use the interactive model before and after the worked examples. Change the inputs, make a prediction, then use the model to test whether your reasoning holds.
Equal-Share Lab
Keep the whole fixed and change how many equal shares it contains.
- Build one example of solve fraction multiplication word problems in the Math Box.
- Change one input and predict the effect before moving the control.
- Explain which mathematical relationship stayed invariant after the change.
Worked examples
Twenty different ways to see the concept work.
2 identical servings each use 1/4 cup. How many cups are used in all?
2 × 1/4 = 2/4Equal fractional groups are multiplication: multiply the whole-number group count by the fraction.
3 identical servings each use 2/5 cup. How many cups are used in all?
3 × 2/5 = 6/5Equal fractional groups are multiplication: multiply the whole-number group count by the fraction.
4 identical servings each use 3/6 cup. How many cups are used in all?
4 × 3/6 = 12/6Equal fractional groups are multiplication: multiply the whole-number group count by the fraction.
5 identical servings each use 1/7 cup. How many cups are used in all?
5 × 1/7 = 5/7Equal fractional groups are multiplication: multiply the whole-number group count by the fraction.
6 identical servings each use 2/8 cup. How many cups are used in all?
6 × 2/8 = 12/8Equal fractional groups are multiplication: multiply the whole-number group count by the fraction.
7 identical servings each use 3/9 cup. How many cups are used in all?
7 × 3/9 = 21/9Equal fractional groups are multiplication: multiply the whole-number group count by the fraction.
2 identical servings each use 1/10 cup. How many cups are used in all?
2 × 1/10 = 2/10Equal fractional groups are multiplication: multiply the whole-number group count by the fraction.
3 identical servings each use 2/4 cup. How many cups are used in all?
3 × 2/4 = 6/4Equal fractional groups are multiplication: multiply the whole-number group count by the fraction.
4 identical servings each use 3/5 cup. How many cups are used in all?
4 × 3/5 = 12/5Equal fractional groups are multiplication: multiply the whole-number group count by the fraction.
5 identical servings each use 1/6 cup. How many cups are used in all?
5 × 1/6 = 5/6Equal fractional groups are multiplication: multiply the whole-number group count by the fraction.
6 identical servings each use 2/7 cup. How many cups are used in all?
6 × 2/7 = 12/7Equal fractional groups are multiplication: multiply the whole-number group count by the fraction.
7 identical servings each use 3/8 cup. How many cups are used in all?
7 × 3/8 = 21/8Equal fractional groups are multiplication: multiply the whole-number group count by the fraction.
2 identical servings each use 1/9 cup. How many cups are used in all?
2 × 1/9 = 2/9Equal fractional groups are multiplication: multiply the whole-number group count by the fraction.
3 identical servings each use 2/10 cup. How many cups are used in all?
3 × 2/10 = 6/10Equal fractional groups are multiplication: multiply the whole-number group count by the fraction.
4 identical servings each use 3/4 cup. How many cups are used in all?
4 × 3/4 = 12/4Equal fractional groups are multiplication: multiply the whole-number group count by the fraction.
5 identical servings each use 1/5 cup. How many cups are used in all?
5 × 1/5 = 5/5Equal fractional groups are multiplication: multiply the whole-number group count by the fraction.
6 identical servings each use 2/6 cup. How many cups are used in all?
6 × 2/6 = 12/6Equal fractional groups are multiplication: multiply the whole-number group count by the fraction.
7 identical servings each use 3/7 cup. How many cups are used in all?
7 × 3/7 = 21/7Equal fractional groups are multiplication: multiply the whole-number group count by the fraction.
2 identical servings each use 1/8 cup. How many cups are used in all?
2 × 1/8 = 2/8Equal fractional groups are multiplication: multiply the whole-number group count by the fraction.
3 identical servings each use 2/9 cup. How many cups are used in all?
3 × 2/9 = 6/9Equal fractional groups are multiplication: multiply the whole-number group count by the fraction.
Practice
Guided practice with hints
014 identical servings each use 3/10 cup. How many cups are used in all?
Hint: Name the quantities and representation first; then choose the operation or comparison that preserves their meaning.
Answer: 4 × 3/10 = 12/10
025 identical servings each use 1/4 cup. How many cups are used in all?
Hint: Name the quantities and representation first; then choose the operation or comparison that preserves their meaning.
Answer: 5 × 1/4 = 5/4
036 identical servings each use 2/5 cup. How many cups are used in all?
Hint: Name the quantities and representation first; then choose the operation or comparison that preserves their meaning.
Answer: 6 × 2/5 = 12/5
047 identical servings each use 3/6 cup. How many cups are used in all?
Hint: Name the quantities and representation first; then choose the operation or comparison that preserves their meaning.
Answer: 7 × 3/6 = 21/6
052 identical servings each use 1/7 cup. How many cups are used in all?
Hint: Name the quantities and representation first; then choose the operation or comparison that preserves their meaning.
Answer: 2 × 1/7 = 2/7
063 identical servings each use 2/8 cup. How many cups are used in all?
Hint: Name the quantities and representation first; then choose the operation or comparison that preserves their meaning.
Answer: 3 × 2/8 = 6/8
Practice
Independent practice
014 identical servings each use 3/9 cup. How many cups are used in all?
Answer: 4 × 3/9 = 12/9
025 identical servings each use 1/10 cup. How many cups are used in all?
Answer: 5 × 1/10 = 5/10
036 identical servings each use 2/4 cup. How many cups are used in all?
Answer: 6 × 2/4 = 12/4
047 identical servings each use 3/5 cup. How many cups are used in all?
Answer: 7 × 3/5 = 21/5
052 identical servings each use 1/6 cup. How many cups are used in all?
Answer: 2 × 1/6 = 2/6
063 identical servings each use 2/7 cup. How many cups are used in all?
Answer: 3 × 2/7 = 6/7
074 identical servings each use 3/8 cup. How many cups are used in all?
Answer: 4 × 3/8 = 12/8
085 identical servings each use 1/9 cup. How many cups are used in all?
Answer: 5 × 1/9 = 5/9
Common mistakes
Learn to catch the error, not just the answer.
Track the size of the fractional unit first; fractions can be combined only when the units are compatible.
Compare complete fraction values with a model, benchmark, common denominator, or cross-product reasoning.
Applications & challenge
Use the idea beyond a single exercise.
Applications
- Scale recipes, measurements, money, and data while preserving the meaning of the unit.
- Compare quantities that are not whole numbers in science, construction, shopping, and measurement.
Challenge problems
6 identical servings each use 2/10 cup. How many cups are used in all?
6 × 2/10 = 12/10
7 identical servings each use 3/4 cup. How many cups are used in all?
7 × 3/4 = 21/4
2 identical servings each use 1/5 cup. How many cups are used in all?
2 × 1/5 = 2/5
3 identical servings each use 2/6 cup. How many cups are used in all?
3 × 2/6 = 6/6
Flashcards
Retrieve it from memory.
Flashcards
Card 1 of 4
Game mode
Grade 5 Math Strategy Sprint
Solve and explain solve fraction multiplication word problems problems accurately, then check each result with a second method.
Practice
Mastery check
014 identical servings each use 3/7 cup. How many cups are used in all?
Answer: 4 × 3/7 = 12/7
025 identical servings each use 1/8 cup. How many cups are used in all?
Answer: 5 × 1/8 = 5/8
036 identical servings each use 2/9 cup. How many cups are used in all?
Answer: 6 × 2/9 = 12/9
047 identical servings each use 3/10 cup. How many cups are used in all?
Answer: 7 × 3/10 = 21/10
052 identical servings each use 1/4 cup. How many cups are used in all?
Answer: 2 × 1/4 = 2/4
063 identical servings each use 2/5 cup. How many cups are used in all?
Answer: 3 × 2/5 = 6/5
074 identical servings each use 3/6 cup. How many cups are used in all?
Answer: 4 × 3/6 = 12/6
085 identical servings each use 1/7 cup. How many cups are used in all?
Answer: 5 × 1/7 = 5/7
Terminology
Words to know
- numerator
- The number of selected equal parts or unit fractions.
- denominator
- The number of equal parts that make one whole.
- equivalent fractions
- Different fraction names for the same numerical value.
- benchmark
- A familiar reference value such as 0, 1/2, or 1 used for comparison.
Continue learning
Connected concepts
Curriculum references
Standards and instructional references
California Mathematics Framework (2023)
Grade-level instructional guidance, mathematical practices, and coherent progression.Common Core State Standards for Mathematics — Grades 4–5
Grade-level expectations for operations, number and fraction work, measurement, data, and geometry.Principles to Actions: Ensuring Mathematical Success for All
Evidence-based emphasis on reasoning, representations, discourse, and conceptual understanding.