About this video
The video finds the number a point marks on a number line between 3 and 4. It counts the ten equal spaces to show each tick mark is one tenth, counts three tenths past 3, and writes the answer as 3.3.
You'll be able to
- work out what each tick mark on a number line stands for by counting equal spaces.
- name a point between two whole numbers in tenths.
- write a number like three and three tenths as a decimal (3.3).
Key words
- tick mark
- A small line on a number line that marks a number.
- tenth
- One of ten equal parts of a whole, written 1/10 or 0.1.
- decimal
- A way to write parts of a whole using a decimal point, like 3.3.
- tenths place
- The first place to the right of the decimal point; it tells how many tenths.
Transcript
- [Voiceover] Where is the point on the number line? Well, here it is, here is the point. But I'm guessing that they're asking not literally just to find it and look at it but what number is this point graphed at. Where is this on the number line? So, one thing we know pretty quickly is the number is between three and four.
It's greater than three but it's not quite four. But to figure out how much greater than three we need to know what these black tick marks represent. So, between three and four there is one, two, three, four, five, six, seven, eight, nine, ten equal spaces. So, each of these distances, each of these equal spaces, is one tenth or one tenth of the distance between three and four.
It's one out of ten equal spaces. So, if that's one tenth and this next space is another one tenth. And then we have to travel one more tenth to get to our point. So, we went three, we know it's three. Plus, one, two, three tenths. Three and three tenths. Or, let's write this as a decimal, let's look at it as a decimal.
If we wanted, we could have our ones place value and then after the ones, the decimal and the tenths. So, for the ones, there's three ones. And how many tenths did we see here? There were three tenths. So, either way we can say three and three tenths or three and three tenths.
Our decimal, our point is 3.3 on the number line.
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