About this video
The tutor counts by tens from 10 to 100 and finds the missing number, 30. Then he uses ten frames, which hold 10 objects each, to show 20 and to make 40.
You'll be able to
- count by tens to 100.
- find a missing number when counting by tens.
- use ten frames to show numbers like 20 and 40.
Key words
- count by tens
- Counting 10, 20, 30, 40 and so on, adding 10 each time.
- ten frame
- A box with 10 spaces that holds 10 objects when it is full.
Transcript
- [Tutor] So we are told let's count by tens and we go 10, 20, blank, 40, 50, 60, 70, 80, 90, 100, what number did we miss? Pause the video, what number did we miss right over here? Well, if we're counting by tens, we would go 10, 20, 30, 40, 50, 60, 70, 80, 90, 100, so we're missing 30, so which choice right over here has 30?
Well, if we scroll down a little bit, we see right there, that is our choice. Let's do another example. So here we are asked which ten frames show 20? A ten frame is just a fancy word for one of these blocks or these frames, that have 10 objects in them, you can see it right over here, one, two, three, four, five, six, seven, eight, nine, 10, so which of these ten frames show 20?
Well, 20 is two groups of 10, so this is 10 and then 20, so that's 20 right over there, choice B is 10, 20, 30, 40, choice C is 10, 20, 30, so we can feel good about choice A. Here we're told drag the ten frames into the box to make 40. So let's see, here this is 10, right over there, then we get another 10, gets us to 20, then another 10 gets us to 30 and then finally another 10 gets us to 40, 10, 20, 30, 40, we're done.
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