Division word problems within 100: How many in each group?
About this video
The video solves a division word problem: 60 carrots are shared evenly into 4 baskets. It writes 4 x blank = 60 or 60 divided by 4, splits 60 into 40 + 20 to get 4 x 10 + 4 x 5 = 4 x 15, so each basket has 15 carrots. It also shows halving twice: 60 divided by 2 is 30, and 30 divided by 2 is 15.
You'll be able to
- write a how-many-in-each-group problem as a multiplication with a blank or as a division.
- use 4 x 10 + 4 x 5 = 4 x 15 to find 60 divided by 4.
- divide by 4 by halving twice.
Key words
- evenly
- Shared so every group gets the same amount.
- distributive property
- You can split a number into parts, multiply each part, and add: 4 x 15 = 4 x 10 + 4 x 5.
- divide
- To split a total into equal groups.
Transcript
- [Instructor] We are told students harvested 60 carrots from the school garden. They placed the carrots evenly into four baskets. How many carrots were in each basket? Pause this video. Have a go at that before we do this together. Okay, so we are going to have four baskets, and then you multiply that times the number of carrots in each basket, and that is going to give you the total number of carrots, that's going to be equal to 60.
You could have also written this as 60... I could write it over here, 60 divided by 4. If I were to divide this evenly into four groups, what would that be equal to? So let's see if we could reason this out. So we know that 4 times 10 is equal to 40, but that doesn't get us all the way there.
We need to get another 20. But we also know that 4 times 5 is going to be equal to 20. So if we add 4 times 10, plus 4 times 5, that's the same thing as 40 plus 20. So that's going to be equal to 60. So I could write this as 4 times 10 plus 4 times 5. Well, another way to think about this is, this is the same thing as 4 times 10 plus 5.
'Cause if we just use the distributive property, if we said 4 times 10, well, that's that part there. And then we have 4 times 5, that is that part there. 4 times 10 plus 4 times 5. So 4 times 10 plus 5 is also equal to 60. And I think you see where this might be going.
What is 10 plus 5? 10 plus 5 is 15. So we just figured out that 4 times 15 is equal to 60. So if there's four baskets and then each of those baskets have 15 carrots... Lemme do that same orange color. Each of them have 15 carrots. Then I'm going to get to 60. Or another way to think about it, 60 divided by 4 is 15.
There's other ways you could have thought about it. If you took 60 divided by 2, if you, you could say, "Oh, I could maybe do that in my head." 6 divided by 2 is 3. So 60 divided by 2 is 30. And then if I divide by 2 again, well, maybe I get to 15. So there's a lot of different ways to think about this.
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