Math Expressions Grade 4, Unit 4: Equations and Word Problems
In this unit, your child writes equations to solve word problems that take more than one step, using a letter for the unknown and checking whether answers make sense. They also find factor pairs, tell factors from multiples, and sort numbers as prime or composite. It follows division with whole numbers and leads into a unit on measurement.
By Robert “Bobby” BarnettMath teacher, parent, and founder of Bobby’s Math Club
What is my child learning in Unit 4?
- Writing equations with a letter for the unknown to solve multistep word problems, then estimating to check that the answer is reasonable. Learn more: Multi-step story problems and leftovers
- Finding all the factor pairs of a number up to 100, listing multiples, and deciding whether a number is prime or composite. Learn more about finding factors and multiples up to 100: Finding factors and multiples up to 100 · Learn more about spotting prime numbers
Sample questions to try together
These are real questions from our practice. Tap the speaker to hear one read aloud, or the light bulb for a hint, and talk about the answer together.
Question 1 of 3
A class of 28 students splits into 4 equal teams for a game. Then 2 new students join one of the teams. How many students are on that team now?
- 9
- 7
- 30
How you can help
- Arrange 24 crackers or blocks into as many different rectangles as you can, and list each factor pair: 1 × 24, 2 × 12, 3 × 8, and 4 × 6.
- Make up a two-step story at the store: we buy 4 packs of 6 juice boxes and the team drinks 15, so how many are left? Ask for an equation with a letter.
- Play "prime or not" on a walk or ride with house numbers or numbers on signs, and ask your child to name a factor pair for any composite number.
Where kids can get stuck
- Missing factor pairs, such as finding 2 × 18 and 3 × 12 for 36 but not 4 × 9 or 6 × 6.
- Mixing up factors and multiples, saying 12 is a factor of 3 when they mean it is a multiple.
- Calling every odd number prime, including 9, 15, and 21, which all have factors besides 1 and themselves.
Practice makes perfect
Bobby's Math Club has practice problems that adapt to your child’s level, each with a detailed explanation and an easy-to-follow video, so your child can build confidence in these skills one step at a time.
Words your child will hear
- equation
- A number sentence with an equal sign showing two amounts are the same, like 35 = 5 × 7.
- unknown
- The number a problem asks you to find, often shown with a letter or a box.
- multistep
- Needing more than one calculation to reach the answer.
- factor
- A number multiplied by another number to make a product, like 4 and 6 in 4 × 6 = 24.
- multiple
- The product of a number and a whole number, like 6, 9, and 12 for 3.
- factor pair
- Two numbers that multiply to make a given number, like 4 and 9 for 36.
- prime number
- A whole number greater than 1 with exactly two factors, 1 and itself, such as 7.
- composite number
- A whole number with more than two factors, such as 9 or 12.
Ready to build your child’s confidence with factors and word problems?
In Bobby's Math Club, your child practices these skills 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.
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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.
Which math standards does Math Expressions Grade 4 Unit 4 cover?
Math Expressions Grade 4 Unit 4 covers these math standards. Each one links to what it means, sample questions, and teaching strategies.
For teachers: Unit names and order vary between editions and districts, so your school’s own materials have the exact sequence. Learn how Bobby's Math Club can help your students grow.