enVision Mathematics Grade 5, Topic 4: Use Models and Strategies to Multiply Decimals
In this unit, your child multiplies decimals, like 3.2 × 4 or 0.6 × 0.5, using grids, place value, and estimation to decide where the decimal point belongs. They also multiply decimals by 10, 100, and 1,000 and notice how the digits shift. It extends whole-number multiplication from the unit before and leads into dividing whole numbers next.
By Robert “Bobby” BarnettMath teacher, parent, and founder of Bobby’s Math Club
What is my child learning in Topic 4?
- Multiplying decimals by 10, 100, and 1,000, so 4.2 × 100 = 420, and seeing each digit shift to the left. Learn more: Multiplying and dividing by 10, 100, and 1,000
- Multiplying decimals by whole numbers and by decimals, like 0.6 × 0.5 = 0.3, and estimating to place the decimal point. Learn more about adding and subtracting decimals to hundredths: Adding and subtracting decimals to hundredths · Learn more about multiplying decimals to hundredths · Learn more about dividing decimals to hundredths
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
Amara's family packs rice for a food bank in bags of 1.5 kilograms. How many kilograms of rice are in 10 bags?
- 0.15 kilograms
- 15 kilograms
- 11.5 kilograms
How you can help
- Price several of one item at the store, like 3 notebooks at $1.75. Ask your child to estimate first, about 3 × $2, then find the exact cost, $5.25.
- Ask what 10 or 100 of something would cost, like a $0.35 sticker. Let your child see the digits shift: $3.50 for 10 and $35 for 100.
- Measure a room or rug in meters, like 2.5 by 1.4. Ask your child to estimate the area, then multiply to find 3.5 square meters.
Where kids can get stuck
- Using the “add a zero” rule on decimals, so 4.2 × 10 becomes 4.20 instead of 42.
- Writing 0.4 × 0.2 as 0.8, not seeing that tenths times tenths gives hundredths, 0.08.
- Skipping the estimate, so an answer of 35 for 2.5 × 1.4 goes unchecked when it should be near 3.
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
- decimal point
- The dot in a number like 4.25 that comes right after the ones place.
- power of 10
- A number made only of 10s multiplied together, like 10, 100 (10 × 10), or 1,000 (10 × 10 × 10).
- exponent
- A small raised number that tells how many times to multiply the base, like the 3 in 10³.
- hundredth
- The place two spots to the right of the decimal point.
- estimate
- A close guess found with easier numbers, used to check whether an answer makes sense.
- product
- What you get when you multiply numbers together.
- factor
- One of the numbers being multiplied, like 6 or 4 in 6 × 4.
Ready to build your child’s confidence with multiplying decimals?
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 enVision Mathematics Grade 5 Topic 4 cover?
enVision Mathematics Grade 5 Topic 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.