Division word problems within 100: How many groups?
About this video
The video solves a division word problem: 52 balloons are tied in groups of 4, so how many groups? It writes the problem as blank x 4 = 52 or 52 divided by 4, then splits 52 into 40 + 12 to find 4 x 10 + 4 x 3 = 52, so there are 13 groups.
You'll be able to
- write a how-many-groups word problem as an unknown times a number or as a division.
- split a number like 52 into 40 + 12 to help me divide.
- find that 52 divided by 4 = 13.
Key words
- divide
- To split a total into equal groups.
- distributive property
- You can split a number into parts, multiply each part, and add: 4 x 13 = 4 x 10 + 4 x 3.
- unknown
- The missing number we are trying to find, shown as a blank.
Transcript
- [Instructor] We are told a party store has 52 balloons. The store owner wants to tie four balloons together in each group to decorate the front windows. How many groups can the store owner make? Pause this video and have a go at this before we do this together.
All right, now let's do this together. So if we had a certain number of groups, so let me write this, number of groups, and if we had that number of groups, times four, times four, that would be the total number of balloons we have, which we know is going to be 52 balloons.
So another way to think about it is we have blank times four is equal to 52, or we could say four times the number of groups blank is equal to 52, or we could say that blank is equal to 52 divided by four. So what do we get for that blank, which is also going to be the same thing as the number of groups?
The number of groups. Well, actually let's go back to this one right over here, four times what is equal to 52? Well, we know that four times 10 is going to get us to 40. So how do we get to 52? Well, we have to get another 12. So another way to think about it is four times what is going to be equal to 40 plus 12.
Well, we know that if you take four times 10, we know that if you take four times 10, you get to 40. And then we also know if you take four times three, you get to 12. So if you take four times four, let me write it this way, four times 10 plus three, that's going to be, we just use the distributive property, that would be four times 10, which is 40, plus four times three plus 12, that is going to be equal to 52, which is exactly what we wanna get to.
So 10 plus three, this is 13. So four times 13 is equal to 52. So blank or the number of groups is 13. Number of groups, 13, times four is truly equal to 52 or 52 divided by four is 13.
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