Multiply and divide by 10, 100, and 1,000
Moving digits by tens is a skill your child will reach for again and again once decimals arrive. It is how 2.5 meters becomes 250 centimeters, how 10 items at $1.25 come to $12.50, and later how scientists write very large and very small numbers. A child who knows the digits move, rather than that you "add a zero," will not be thrown when 3.6 × 10 is 36.
In this video, your child will learn to multiply and divide by ten, hundred, thousand.
The lesson stops at each question for your child's answer.
Three problems, each a little harder
Each problem is worked step by step. Your child will solve the last one before Bobby shows how.
Example 1
6 × 10² = ?
Example 2
45 ÷ 10² = ?
Your child's turn
3.2 × 10³ = ?
The three key steps
- 1Count zeros, or read the power.
- 2×: move digits that many left
- 3÷: move digits that many right
Mistakes to listen for
- Using the "add a zero" rule on decimals, so 4.2 × 10 becomes 4.20, which is still 4.2, instead of 42.
- Moving the decimal point the wrong way when dividing, so 6.5 ÷ 10 becomes 65 instead of 0.65.
- Losing count of zeros when the number already ends in one, writing 50 × 100 as 500 instead of 5,000.
The lesson shows every step, so your child sees why it works. Read our parent's guide to multiplying and dividing by 10, 100, and 1,000 →
Is your child ready to practice what they've learned?
Bobby's Math Club offers unlimited practice for free.
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More 5th grade Numbers & Place Value, with questions your child answers along the way.
Questions parents ask
Does my child need an account to watch?
No. You can watch this on any device at any time. If your child would like to practice multiplying and dividing by 10, 100, and 1,000, and you'd like parent-friendly reports on your child's progress and growth, you can join Bobby's Math Club for unlimited free practice.
What happens when my child answers a question?
A right answer gets a cheer, and the lesson carries on. If your child isn't sure, they can tap "I don't know yet", and Bobby gives the answer and shows another example. Nothing is scored or stored.
Is this the same lesson that's on YouTube?
Yes. Here, the lesson stops at each question and waits for your child to answer. On YouTube, each question stays on screen for a few seconds, and then the lesson plays on.
Where can I learn more?
There's a short, kid-friendly lesson like this one for every Pre-K to 5th grade math skill, all in our video library. Our parent's guide to multiplying and dividing by 10, 100, and 1,000 has more on where kids get stuck and how you can help at home. In the club, your child practices at just the right level, about five minutes a day, and you get parent-friendly reports as they grow. Learn more about how it works →
Practice multiplying and dividing by 10, 100, and 1,000
Questions at your child's level, about five minutes a day, on multiplying and dividing by 10, 100, and 1,000 and whatever PK-5 skills they need to develop. Unlimited practice, free forever.
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