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Current time:0:00Total duration:2:55

Voiceover:What I want to
do in this video is think a little bit about what
numbers really represent. Let's say someone were to
write down the number 25. So what does this really mean? Well the five here, this
is in the one's place so it literally represents five ones. And this two right over here, this is in the 10's place, so let me write that down. That's the 10's place,
that's the one's place, so this represents two 10s. What do I mean by that? Well another way to write this is this two represents two 10s, just
let me write that down. This is equal to two 10s plus five ones. Now what are two 10s? Well that's literally if
you can imagine a 10 being a block of 10 things,
so you could imagine if this was a 10 right over here. Let me copy and paste this, so copy. So this is going to be the same thing, this is going to be
equal to, you have your two 10s, so one 10 and two tens, so you have your two 10s. So that's your two 10s right over there, that really represents
20 plus your five ones. Plus your five ones. Well if this is a one
right over here, and I'm just representing it
as kind of one vertical bar, five ones are going to look like, your going to have one,
two, I think you see where this is going,
three, four, and five. And so these are all different ways of representing the same quantity. 25 is two 10s and five ones. This two is in the 10's place, the five is in the one's place. So two 10s plus five
ones, so you could then view it as two groups of 10 plus five ones right over here. And what's this going
to be the same thing as? Well two groups of 10, this
is the same thing as 20 and this over here is equal to five. So once again, all ways to represent 25. You can view this as two
10s plus five ones or you can view this as 20,
let me write this down, 25 you could view because
this two is two 10s that represents 20 plus the five ones.