About this video
The video graphs 0.04 on a number line that runs from 0 to 0.1. It shows that splitting one tenth into ten equal pieces makes hundredths, because a tenth of a tenth is 1/100, and then counts four hundredths from 0.
You'll be able to
- explain why a tenth of a tenth is one hundredth.
- work out that each space on a 0 to 0.1 number line with ten spaces is 1/100.
- graph a number like 0.04 by counting hundredths.
Key words
- tenth
- One of ten equal parts of a whole, written 1/10 or 0.1.
- hundredth
- One of a hundred equal parts of a whole, written 1/100 or 0.01.
- place value
- The value a digit has because of where it sits in a number.
- hundredths place
- The second place after the decimal point; it tells how many hundredths.
Transcript
- [Voiceover] Graph 0.04 on the number line. So here we have this number line that goes from zero to 0.1, or 1/10, and between zero and 1/10, we have one, two, three, four, five, six, seven, eight, nine, ten equal spaces. So each of these spaces represents 1/10th of the distance, is one out of ten equal spaces.
Or we could say, it is 1/10th of this tenth, it's a tenth of the way to 1/10th. That's a little bit tricky, maybe let's pause and look at that visually and think about what does a tenth of a tenth really mean. So here I have already drawn a picture that's divided into 10 equal pieces.
And if we shade one of them, then we're shading 1/10th. This right here is 1/10th. And this amount right here is what the number line showed, the whole number line showed 1/10th. But then we had divided that tenth into 10 equal pieces, so if we split that 10 into 10 equal pieces, we're gonna have something like this.
So here again this top row would represent the entire tenth, from the whole number line, but each little piece would be 1/10th of that whole tenth. Or, so this is what each little piece on the number line represents, or we could say that's 1/100th, a tenth of a tenth is a 1/100th, 'cause when you divide 10 into 10 equal pieces, you're gonna end up with 100 pieces.
So a tenth of a tenth is a 1/100th. So looking back at the number line, now we know that this distance, a tenth of our tenth, is 1/100th. And we want to graph 0.04. Well this four right here, let's think about place value. The zero's in the ones, the next zero in the tenth, and this four is in the hundreds, so we could call this four hundredths, or even the fraction, 4/100.
So if one of these lengths is 1/100 and we wanna go 4/100, then we're gonna need to go four of these lengths. One, two, three, four of these lengths would be four of the hundredths, or 0.04.
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