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3rd grade
Course: 3rd grade > Unit 1
Lesson 1: Multiplication as equal groupsMultiplication as repeated addition
CCSS.Math:
Sal related multiplication problems to equivalent repeated addition problems.
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- who is the person teaching us?🤨(44 votes)
- sal is the person
teaching us(4 votes)
- - [Instructor] So as some of you already know, 0:00I really enjoy eating a good avocado, 0:01which, despite its appearance 0:05that it looks like a vegetable, 0:06but it's actually a fruit. 0:08
•Current transcript segment:And let's say that I eat two avocados per day, 0:09and I eat two avocados per day for six days. 0:14Now, there's a couple of ways that I could think 0:18about how many avocados did I eat? 0:20I could say, hey, I eat two a day, 0:23and I'm going to do that for six days, 0:25so I'm gonna add six twos together. 0:27So it'll be two, plus two, plus two, plus two, plus two, 0:29plus two, I have six twos right over there. 0:35And then I can add them together. 0:38And we could say two plus two is four. 0:40You add another two, you get to six. 0:42You add another two, you get to eight. 0:44Yet another two to get to 10. 0:45Yet another two, you get to 12. 0:46And that all is fine, but there's an easier way 0:49to express this repeated addition. 0:53One way is to view it as multiplication. 0:56Instead of just writing out six twos 1:00and adding them together, mathematicians have come up 1:03with a neater way of writing that. 1:06Let's say, okay, we're going to add up a bunch of twos. 1:08How many twos are we going to add up? 1:11We're going to have six of those twos, 1:13and we need to come up with some type of a symbol for it. 1:15So we will use this X-looking thing. 1:17And so, six times two can be viewed 1:20as repeated addition in exactly this same way. 1:24So six times two would be equal to 12. 1:27And we could go the other way around. 1:32If someone were to ask you, what is four times three? 1:33Pause this video and see if you can write it out 1:39as repeated addition, like we saw up here. 1:42Well, one way to interpret this is to say, 1:46this is four threes, so we could say this is equal 1:48to three, plus three, plus three, plus three. 1:51And three plus three is six, six plus three is nine, 1:56nine plus three is equal to 12. 1:59You might be familiar with skip counting, 2:02and you would say three, six, nine, 12. 2:03Just out of curiosity, 2:07what do you think three times four is going to be? 2:08Pause this video and try to represent it 2:13as repeated addition, and then see what you come up with. 2:15Well, we can interpret this as three fours. 2:19And so, we could say this is going 2:23to be four, plus four, plus four. 2:25And if we skip count fours, we'd have four, eight, 12, 2:28(chuckles) I was about to go to 16, four, eight, 12. 2:32So this is going to be 12. 2:35So this is interesting, at least for this example, 2:37for these two examples, I got to the same thing. 2:41Four times three got me the same result 2:43as three times four, interesting. 2:46I wonder if that's always true. 2:49But anyway, big picture from this video is 2:51that you can view multiplication as repeated addition. 2:54(16 votes)- Wowwwwwww thats long! i cant even read it!(2 votes)
- what is 1000000+2000000=(11 votes)
- Come on it is 30000000(1 vote)
- yall want something from the gas station?(10 votes)
- you cant skip by 102,S(3 votes)
- Right ur Right!(4 votes)
- This is a good explanation of repeated addition. I personally think that if the teacher teaching us could make the lessons funnier it would make more children willing to listen.(4 votes)
- 3000 + 3000= 6000 ...(3 votes)
- why is the times sign a x thingy(3 votes)
- Video transcript
- [Instructor] So as some of you already know, I really enjoy eating a good avocado, which, despite its appearance that it looks like a vegetable, but it's actually a fruit. And let's say that I eat two avocados per day, and I eat two avocados per day for six days. Now, there's a couple of ways that I could think about how many avocados did I eat? I could say, hey, I eat two a day, and I'm going to do that for six days, so I'm gonna add six twos together. So it'll be two, plus two, plus two, plus two, plus two, plus two, I have six twos right over there. And then I can add them together. And we could say two plus two is four. You add another two, you get to six. You add another two, you get to eight. Yet another two to get to 10. Yet another two, you get to 12. And that all is fine, but there's an easier way to express this repeated addition. One way is to view it as multiplication. Instead of just writing out six twos and adding them together, mathematicians have come up with a neater way of writing that. Let's say, okay, we're going to add up a bunch of twos. How many twos are we going to add up? We're going to have six of those twos, and we need to come up with some type of a symbol for it. So we will use this X-looking thing. And so, six times two can be viewed as repeated addition in exactly this same way. So six times two would be equal to 12. And we could go the other way around. If someone were to ask you, what is four times three? Pause this video and see if you can write it out as repeated addition, like we saw up here. Well, one way to interpret this is to say, this is four threes, so we could say this is equal to three, plus three, plus three, plus three. And three plus three is six, six plus three is nine, nine plus three is equal to 12. You might be familiar with skip counting, and you would say three, six, nine, 12. Just out of curiosity, what do you think three times four is going to be? Pause this video and try to represent it as repeated addition, and then see what you come up with. Well, we can interpret this as three fours. And so, we could say this is going to be four, plus four, plus four. And if we skip count fours, we'd have four, eight, 12, (chuckles) I was about to go to 16, four, eight, 12. So this is going to be 12. So this is interesting, at least for this example, for these two examples, I got to the same thing. Four times three got me the same result as three times four, interesting. I wonder if that's always true. But anyway, big picture from this video is that you can view multiplication as repeated addition.(3 votes) - why is it kicking me out(4 votes)
- I feel so bad😞, you OK?🖤🖤🖤😘😚🤨😑😮😥(1 vote)
Video transcript
- [Instructor] So as
some of you already know, I really enjoy eating a good avocado, which, despite its appearance that it looks like a vegetable, but it's actually a fruit. And let's say that I eat
two avocados per day, and I eat two avocados
per day for six days. Now, there's a couple of
ways that I could think about how many avocados did I eat? I could say, hey, I eat two a day, and I'm going to do that for six days, so I'm gonna add six twos together. So it'll be two, plus two,
plus two, plus two, plus two, plus two, I have six
twos right over there. And then I can add them together. And we could say two plus two is four. You add another two, you get to six. You add another two, you get to eight. Yet another two to get to 10. Yet another two, you get to 12. And that all is fine,
but there's an easier way to express this repeated addition. One way is to view it as multiplication. Instead of just writing out six twos and adding them together,
mathematicians have come up with a neater way of writing that. Let's say, okay, we're going
to add up a bunch of twos. How many twos are we going to add up? We're going to have six of those twos, and we need to come up with
some type of a symbol for it. So we will use this X-looking thing. And so, six times two can be viewed as repeated addition in
exactly this same way. So six times two would be equal to 12. And we could go the other way around. If someone were to ask you,
what is four times three? Pause this video and see
if you can write it out as repeated addition, like we saw up here. Well, one way to interpret this is to say, this is four threes, so
we could say this is equal to three, plus three,
plus three, plus three. And three plus three is
six, six plus three is nine, nine plus three is equal to 12. You might be familiar with skip counting, and you would say three, six, nine, 12. Just out of curiosity, what do you think three
times four is going to be? Pause this video and try to represent it as repeated addition, and then
see what you come up with. Well, we can interpret
this as three fours. And so, we could say this is going to be four, plus four, plus four. And if we skip count fours,
we'd have four, eight, 12, (chuckles) I was about to
go to 16, four, eight, 12. So this is going to be 12. So this is interesting,
at least for this example, for these two examples,
I got to the same thing. Four times three got me the same result as three times four, interesting. I wonder if that's always true. But anyway, big picture from this video is that you can view multiplication
as repeated addition.