About this video
Sal plots six numbers on a number line: 5, 1/3, -1.2, 0, -2 1/4 and 4.1. He finds the nearest whole numbers first, then moves part of the way to the next whole number, remembering that negative numbers sit to the left of zero.
You'll be able to
- plot fractions and decimals between two whole numbers on a number line.
- plot negative fractions and decimals by moving left past the nearest negative integer.
- explain why -1.2 is to the left of -1.
Key words
- number line
- A line where every point stands for a number, with bigger numbers further to the right.
- negative number
- A number less than zero, placed to the left of zero on the number line.
- mixed number
- A whole number and a fraction together, like 2 1/4.
Transcript
- [Voiceover] Plot the following numbers on the number line. The first number we have here is five, and so five is five to the right of zero, five is right over there. That's our five. Then we get 1/3. 1/3. So 1/3 is between zero and one. We can actually split this into thirds.
So that would be 1/3, 2/3, and then 3/3, which is one, so 1/3 is going to sit right over there. It's 1/3 of the way from zero to one, that's 1/3. Let me write that. That's 1/3 right over there. Then we have negative 1.2. I'll do that in this blue color. Negative 1.2. So, negative one is right over here.
This is more negative than negative one. It's negative 1.2. It's negative one, and then another .2, so it's going to be right over here. This is negative 1.2. Zero is pretty straight forward. Zero is right over there. It's even labeled for us at zero. Five was labeled for us too at five.
Then we have negative two and 1/4. So let's go to negative two. Negative two is here, and it's going to be more negative than negative two. It's negative two and then another another negative 1/4. So it's negative two, and then we go 1/4 of the way to negative three.
So negative 2 and 1/4 is going to be right over here. So negative two and 1/4. And then finally we have 4.1. 4.1. So four is right over here. .1 is another tenth greater than four, another tenth on the way to five. So four and 1/10 is going to be right over here. 4.1.
4.1. And we are done.
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