About this video
The video places decimals, including a negative one, on a number line marked in tenths. It finds -0.6 just past -0.5, 1.9 one tenth less than 2, and 0.5 halfway between 0 and 1, stressing the need to check the scale first.
You'll be able to
- read the scale on a number line marked in tenths.
- place positive and negative decimals on a number line.
Key words
- scale
- How much each mark on a number line is worth.
- tenth
- One of ten equal parts of 1, written 0.1.
- negative decimal
- A decimal less than zero, like -0.6, to the left of zero.
Transcript
We're asked to move the orange dot to negative 0.6 on the number line. So the dot right now is at 0. And let's see, this is negative 2. This is positive 2. So each of these big slashes look like it's 1. So this would be negative 1, negative 2. This right over here would be negative 0.5.
So we're going to go a little bit more negative than negative 0.5. That would be negative 0.6. We want to go another tenth. And so that looks right at about negative 0.6. Let's do a couple more of these. Move the orange dot to 1.9 on the number line. So it seems like we have the same scale as in the previous example.
This gets us to 1. In fact, this is 0.5, 1, 1.5. And 1.9 is only going to be a tenth less than 2. So it's going to be-- let's see, that's 2, so a tenth less than that. And I'm assuming that it's locking us to the tenths. And it looks like it is, so that looks pretty close to 1.9.
Let's do one more of these. Move the orange dot to 0.5 on the number line. Well, once again, we have the same scale. It's important to always check the scale. And this right over here is 1. So 0.5 would be halfway, so that little small mark right over there.
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