5th Grade · Number & Operations - Fractions
5.NF.B.6: Solve word problems that multiply fractions and mixed numbers
5.NF.B.6 is a 5th grade Common Core math standard in Number & Operations - Fractions. Here’s what it really covers, and how you can help your students learn it.
By Robert “Bobby” BarnettMath teacher, parent, and founder of Bobby’s Math Club
The standard
Solve real world problems involving multiplication of fractions and mixed numbers, e.g., by using visual fraction models or equations to represent the problem.
In plain words
Solve word problems that multiply fractions and mixed numbers.
Sample questions from student practice
These questions from Bobby's Math Club are the kinds of questions your students will see. You can try answering them to see what a student might see.
Question 1 of 3
A baby giraffe is 6 feet tall. Its mother is 2 1/2 times as tall as the baby. How tall is the mother?
- 8 1/2 feet
- 12 feet
- 15 feet
Where students can get stuck
- Multiplying whole numbers and fractions separately, so 2 1/2 × 1 1/2 becomes 2 1/4 instead of 3 3/4.
- Adding when the problem says "half of," so half of 3/4 of a pizza becomes 1 1/4 instead of 3/8.
- Skipping the check for a sensible answer, so they accept that half of 6 1/2 yards of fabric is more than 6 yards.
Effective teaching strategies
- Have students draw an area model for 2 1/2 × 1 1/2, split it into four rectangles, and add the four areas.
- Ask students to draw 3/4 of a rectangle, take half of that shaded part, and write the multiplication sentence that matches the picture.
- Build the habit of estimating first, such as expecting half of 6 1/2 yards to be about 3 yards, and check that the final answer is close.
Units that teach this standard
Find where 5.NF.B.6 lands in the program you teach. Each unit has a guide written for families. Unit names and order vary between editions and districts, so your school’s own materials have the exact sequence.
Bridges in Mathematics
enVision Mathematics
Everyday Mathematics
i-Ready Classroom Mathematics
Illustrative Mathematics
Math Expressions
Don’t see your curriculum? Contact Bobby and we’ll see if we can help!
Share it with families
Families can read Multiplying fractions in real life, like recipes for a plain-language look at this skill, with three questions to try together and ideas for helping at home.
Help every student practice fractions at home
In Bobby's Math Club, students practice at just the right level, with a hint when they need one, a clear explanation after every question, and kid-friendly videos. Unlimited practice is free for every family.
See how it works for teachers
Written by Robert “Bobby” Barnett
Bobby is an award-winning math teacher, the author of Meet Every Learner’s Needs, and the father of two elementary-school math learners. He uses Bobby’s Math Club with his own kids a few times every week. Learn more or contact Bobby.