Finding consecutive multiples (1,000 and 10,000)
About this video
Sabrina walked about 80,000 steps, and three points A, B and C sit between 70,000 and 80,000 on a number line. Sal explains that points less than halfway round to 70,000, while point C is more than halfway, so it is closer to 80,000 and could show Sabrina's steps.
You'll be able to
- explain what 'about 80,000' means.
- use the halfway point between 70,000 and 80,000 to decide which ten thousand a point is closer to.
- round a number to the nearest 10,000.
Key words
- estimate
- A close guess that is not exact.
- round
- To change a number to the nearest ten, hundred, thousand or ten thousand.
- halfway point
- The middle between two numbers, like 75,000 between 70,000 and 80,000.
Transcript
- [Instructor] We're told Sabrina walked about 80,000 steps in a week. Which point on the number line could represent how many steps Sabrina walked? So pause this video, and have a go before we work on this together. All right, so it looks like they've labeled three points, and they are all between 70,000 and 80,000.
And when they say about 80,000 steps, they're saying it's not exactly 80,000, but if we were to estimate, if we were to round, then we would get to 80,000. Now if we have three points that are between 70 and 80,000, the ones that are less than halfway of the way between 70 and 80,000, they would round back to 70,000.
Or another way to think about it, if you're rounding to the nearest 10,000, point A and B would round to 70,000. But we see that point C is more than halfway. This is a halfway point right over here. C is more than halfway from 70,000 to 80,000. Another way to think about it is closer to 80,000 than 70,000.
And so if you had to estimate this, or say what was about, and round to the nearest to 10,000, you would go to 80,000. And so that's why I like point C.
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