Dividing a decimal by a whole number on the number line
About this video
This video uses a number line to find 0.6 ÷ 2. Going from 0 to 6/10 in two equal jumps means each jump is 3/10, so 0.6 ÷ 2 = 0.3. It also explains that 6 of anything split into two equal groups gives 3 of that thing.
You'll be able to
- use equal jumps on a number line to divide a decimal by a whole number.
- explain why 6/10 ÷ 2 = 3/10.
Key words
- number line
- A line with numbers in order, used to show jumps and distances.
- tenths
- Equal parts made when you split one whole into 10; 0.6 is 6 tenths.
- equal jumps
- Jumps on a number line that are all the same size.
Transcript
- [Instructor] In this video, we're going to try to figure out what 0.6 or 6/10 divided by two is. And I'll give you a little bit of a hint. We have 6/10 plotted on the number line right over here. And so one way to think about it is, if I wanted to go from zero to 6/10 in two jumps, how big would each of those jumps have to be?
Pause this video and try to figure that out on your own before we work through it together. All right, so as I mentioned, one way to think about it is how can I go from zero to 6/10 in two jumps? Two equal jumps, I should say. Well, if we just eyeball it right over here, I could do one jump like that and then another jump like that.
So I did one jump and then two jumps. And so one way to think about it is we've divided 6/10 into two jumps, and each of those jumps are how far? Well, each of those jumps are one, two, 3/10. So this is 3/10 or I could write it like this, 3/10. We have another one, two, 3/10.
So this is going to be equal to 3/10. And we've thought about it in other ways. If you have six of something and you divide it by two, you're going to have two groups of three of that something. So if you have 6/10, and you wanna put it into two equal groups, well, each of those groups are going to be 3/10.
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