5.NF.4: Multiplying Fractions

I can multiply a fraction or whole number by a fraction using visual models and equations.

What Your Child Needs to Know

This standard focuses on helping your child multiply fractions by fractions and whole numbers by fractions. Students will learn to use the standard algorithm (multiply numerators, multiply denominators) and understand what fraction multiplication means conceptually through visual models.

This standard builds on previous knowledge of fractions and multiplication with whole numbers. Mastering fraction multiplication will help your child with more advanced concepts like area, volume, and algebraic thinking in later grades.

Real World Practice

Visual models and hands-on activities

Visual Models for Multiplying Fractions

1. Area Model

Draw a rectangle with sides representing the fractions being multiplied. For 2/3 × 4/5, draw a rectangle with width 2/3 and height 4/5. Divide the width into 3 equal parts (shade 2) and the height into 5 equal parts (shade 4). The total rectangle is divided into 15 equal parts, with 8 parts shaded, showing that 2/3 × 4/5 = 8/15.

2. Fraction of a Fraction

Draw a rectangle representing one whole. Divide it horizontally into the denominator of the first fraction (e.g., 3 parts for 2/3). Shade the numerator (2 parts). Then divide each section vertically into the denominator of the second fraction (e.g., 5 parts for 4/5). Shade the numerator (4 parts) in each horizontal section. Count the total shaded squares out of the total squares to find the product.

3. Number Line Model

Use a number line to show that multiplying by a fraction less than 1 results in a smaller number. For 3/4 × 2/3, start at 0, mark 2/3, then find 3/4 of that distance (which is 1/2).

4. Fraction Circles

Use fraction circle pieces to physically model multiplication. For 1/2 × 3/4, take 3/4 of a circle, then find 1/2 of that amount (which is 3/8 of the whole circle).

Everyday Activities

1. Cooking with Fractions

When cooking, practice multiplying fractions to adjust recipes. "If this recipe calls for 3/4 cup of flour, but we want to make 2/3 of the recipe, how much flour do we need?" (3/4 × 2/3 = 1/2 cup)

2. Fraction Art Project

Create a colorful grid on paper. Shade different fractions of each section to represent multiplication problems. For example, shade 2/3 of a section, then shade 1/2 of the shaded portion to show 2/3 × 1/2 = 1/3.

3. Fraction Card Game

Create cards with fractions. Players draw two cards and multiply the fractions. The player with the largest product wins the round. This makes practice fun and competitive.

4. Area Calculations

Measure rooms or objects in your home using fractions of feet or meters. Calculate areas by multiplying the fractional measurements. "If this rug is 2 1/2 feet by 3 3/4 feet, what is its area?" This connects fraction multiplication to real-world measurements.

Quick Checks

Strategies and quick activities

Strategies When Your Child Struggles

1. Multiplication Rule Reminder

Create a simple reminder: "To multiply fractions, multiply the tops (numerators) and multiply the bottoms (denominators)." Have your child repeat this rule before solving problems. This helps reinforce the procedure.

2. Simplify Before Multiplying

Teach your child to look for common factors between numerators and denominators before multiplying. For example, in 2/3 × 6/8, they can simplify 6/8 to 3/4 first, then multiply 2/3 × 3/4. This makes the calculation easier and reduces the need for simplifying afterward.

3. Real-World Context

Frame problems in real-world contexts: "If you have 3/4 of a pizza and eat 2/3 of it, how much of the whole pizza did you eat?" This helps make the abstract concept more concrete and meaningful.

4. Draw First Approach

Encourage your child to draw a picture for each multiplication problem before attempting to solve it mathematically. This helps build conceptual understanding of what fraction multiplication actually means.

5. Check with Estimation

Teach your child to estimate the answer first. When multiplying fractions less than 1, the product will be smaller than either factor. This helps catch errors and builds number sense.

5-Minute Activities

Activity 1: Fraction Multiplication Flash Cards

Create flash cards with fraction multiplication problems on one side and the answers on the other. Practice for 5 minutes daily to build fluency with the standard algorithm.

Activity 2: Visual Model Match

Give your child a fraction multiplication problem and ask them to draw a visual model to represent it. This reinforces the conceptual understanding of what multiplication means.

Activity 3: Real-World Problem Creation

Give your child a fraction multiplication problem (like 2/3 × 3/4) and ask them to create a real-world scenario that would be solved using this multiplication. This helps them connect the abstract operation to concrete situations.

Activity 4: Simplification Race

Give your child a fraction multiplication problem where the answer can be simplified. Time how quickly they can solve it and simplify the result correctly. This builds both procedural fluency and the habit of simplifying answers.

Check Progress

Track improvement

Mid-Year Expectations

By the middle of 5th grade, your child should be able to:

  • Multiply fractions using the standard algorithm (multiply numerators, multiply denominators)
  • Simplify fraction products when possible
  • Create simple visual models to represent fraction multiplication
  • Solve basic word problems involving fraction multiplication

End-of-Year Expectations

By the end of 5th grade, your child should be able to:

  • Multiply fractions and mixed numbers fluently
  • Create detailed visual models for fraction multiplication
  • Solve complex word problems involving fraction multiplication
  • Explain the conceptual meaning of fraction multiplication

Mastery Signs

Your child has mastered this standard when they can consistently:

  • Multiply fractions correctly using the standard algorithm
  • Simplify fraction products when possible
  • Create visual models to represent fraction multiplication
  • Apply fraction multiplication to solve real-world problems
  • Explain what fraction multiplication means conceptually
  • Recognize that multiplying by a fraction less than 1 results in a smaller number

Questions to Ask:

Ask your child to solve these problems and explain their process:

  • 2/3 × 4/5 = ?
  • 3/4 × 2/3 = ?
  • 2 1/2 × 1/3 = ?

Ask them to explain why multiplying by a fraction less than 1 makes the answer smaller.

Differentiation

Support for all learning levels

Below Grade Level

Practice problems focusing on simple fraction multiplication with visual supports and step-by-step guidance.

📥 Download Practice Worksheet

At Grade Level

Standard practice with multiplying fractions and applying the skill in various contexts.

📥 Download Grade Level Worksheet

Above Grade Level

Advanced problems involving multi-step fraction multiplication in complex real-world contexts.

📥 Download Challenge Worksheet