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## Topic A: Multiplication and the meaning of the factors

Current time:0:00Total duration:3:33

# Multiplication as equal groups

CCSS.Math:

## Video transcript

I have these three star patches,
I guess you could call them, right over here. And so I could say, if I had
one group of three star patches, how many star patches do I have? So I literally have one
group of three star patches. Well, that means that I
have three star patches. 1, 2, 3. This is my one group of three. Now let's make it a little
bit more interesting. Let's say that I had two groups. Let's say that I had
two groups of three. So that's one group, and
then here's a second group. Here's two groups of three. So how many total star
patches do I have now? Well, I have two
groups of three. Or another way of thinking
about it is this is 3 plus 3. This is equal to 3 plus
3, which is equal to 6. So we see 1 times 3--
one group of 3 is 3. Two groups of 3, which is
literally two 3's, is 6. Let's make it even
more interesting. Let's have three groups of 3. Now, what is this
going to be equal to? Well, it's three groups of 3. So I could write this as
three groups, 3 times 3. And how many of these star
patches do I now have? Well, this is going
to be 3 plus 3 plus 3. It's going to be
3 plus 3 plus 3. Notice I have three 3's. I have two 3's. I have one 3. So this is 3 plus 3
plus 3 is equal to 9. And you can count them. 1, 2, 3, 4, 5, 6, 7, 8, 9, or
you could just count by 3's. 3, 6, 9. And I think you see
where this is going. Let's keep incrementing it. Let's get four groups of 3. So let's think about
what 4 times 3 is. 1, 2, 3, and 4. This right over here
is four groups of 3. We could write this
down as 4 times 3, which is the same thing
as 3 plus 3 plus 3 plus 3. Notice I have four 3's. One 3, two 3's,
three 3's, four 3's. One 3, two 3's,
three 3's, four 3's. So we get 3, 6, 9, 12. So what I encourage
you to do now, now that the video is almost
over, is to keep going. I want you to figure out what
5 times 3 is, and 6 times 3, and 7 times 3, and 8 times 3,
and 9 times 3, and 10 times 3. And I'll give you a little hint. You don't always have to
draw the star patches, but it's nice to visualize it. We saw 4 times 3 is
literally four 3's. Well, 5 times 3 is
going to be five 3's. So 2, 3, 4, 5. Which is equal to
3, 6, 9, 12, 15. So I encourage you to think
about what all of these are after this video is done.