Representing multi-step problems: strip diagrams
About this video
A fruit stand has 556 apples, sells 432, and shares the rest equally into 4 baskets. The video builds a strip diagram: the whole strip is 556, one part is the 432 sold, and the leftover part is split into four equal parts, each labelled a. To find a, you subtract 556 - 432 and then divide the result by 4.
You'll be able to
- draw a strip diagram for a two-step word problem.
- show a part taken away and an amount split into equal groups on a strip diagram.
- use a strip diagram to plan the steps to solve a problem.
Key words
- strip diagram
- A drawing of rectangles (strips) that shows how amounts in a word problem fit together.
- total
- The whole amount you start with, here 556 apples.
- remaining
- What is left over after some is taken away.
- divide equally
- Split an amount into groups that are all the same size.
Transcript
- [Instructor] We're told a fruit stand has 556 apples. They sell 432 apples. The owner divides the remaining apples equally into four baskets to donate. Which strip diagram shows a way to find a, the number of apples in each basket? So pause this video, have a go at this before we do this together.
And actually let me scroll down a little bit so you can see the bottom of choice C. All right, now let's work on this together. So what I like to do is not even look at this and just think about how I would make a strip diagram. So what I would do is I would start with the total number of apples, 556.
Maybe I'll do it right over here. I'll do it here. So let's say that this is the total that I start with, 556 apples. They sell 432 apples and have some amount left over. So this is the amount that we started with, and then they sell 432 apples. So let me see what 432 looks like.
So 432 would look something like this. I'm approximating it. So this is 432. And then there's going to be some leftover after they sell that 432. So this is the amount that's left. And then they tell us that they divide the remaining apples equally into four baskets to donate.
So we would divide this equally into four baskets. And if a is the number in each basket, this would be a, this would be a, this would be a, and that would be a. And the way I just drew it, it's pretty clear that that would be choice A. Now, how would I use this to actually calculate it?
Well, the first thing I would do is I would figure out what 556 minus 432 is. Let me do that in a darker green 'cause have trouble seeing that. So 556 minus four 432, 432. That would give me what's left over. And then to figure out a, I would divide all of that into four equal chunks.
So this is going to be equal to each of these as right over there.
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