Solving word problems involving multiplicative comparison
About this video
This video solves a multi-step word problem about Ella's muffins and cookies. It uses 'times as many' to find this fall's cookies (2 x 12 = 24), next fall's muffins (3 x 12 = 36) and next fall's cookies (5 x 24 = 120), then adds to get 156 baked goods.
You'll be able to
- turn 'times as many' into a multiplication.
- organise a multi-step word problem in a table.
- use the distributive property to multiply, like 5 x 24 = 5 x 20 + 5 x 4.
Key words
- times as many
- A comparison that tells you to multiply, like 2 times as many as 12 is 24.
- distributive property
- Splitting a number to multiply in parts, like 5 x 24 = 5 x 20 + 5 x 4.
- total
- The amount you get when you add everything together.
Transcript
- [Tutor] We're told, "This fall, Ella baked 12 muffins and 2 times as many cookies for a school craft fair. Next fall, she plans to bake 3 times as many muffins and 5 times as many cookies to meet higher demand. How many totaled baked goods does Ella plan to make next fall?"
Pause this video and try to do this yourself before we do this together. Okay, so now let's do this together. There's two things that she's baking, she's baking cookies. Cookies, actually, lemme start with the muffins 'cause that's the first thing they mentioned.
She's baking muffins, and I'll do it in another color, and she's baking cookies. And then there is this fall, there is This Fall, and then there is next fall, Next Fall. So this fall, we know that Ella baked 12 muffins. So 12 muffins, and 2 times as many cookies, 2 times as many cookies, so how many cookies is that going to be?
Well, it's going to be 12 times 2, because it's two times as many, so this is gonna be 24 cookies. Now next fall, she plans to make 3 times as many muffins, 3 times as many muffins. So let's see, that's gonna be 3 times 12, 3 times 12, which is equal to 36 muffins next fall and 5 times as many cookies to meet higher demand.
So it's gonna be 5 times the number of cookies that she made, and to be very clear, they could have said 5 times as many cookies as she made in the fall, but I think that's somewhat there, so let's see. so 5 times as many cookies the next year, so then that is 5 times the amount that she is going to make this fall, so 5 times 24.
And this is going to be the same thing if you, you might be able to do this in your head, or you might say this is the same thing as 5 times 20 plus 4, which is going to be the same thing as 5 times 20, I'm just doing the distributed property here, 5 times 20 plus, 5 times 4, 5 times 4, which is going to be equal to 100.
And adding to that 20, this is going to be equal to 120. So then if you add up the total to baked goods, Ella plans to make next fall, total baked goods for next fall, that's going to be the number of muffins, plus the number of cookies. So it's going to be 120 plus 36, which is equal to, you could add this up, and you'd get 156.
0 plus 6 is 6, 2 plus 3 is 5, and then you bring down that 100, so we have 156 total baked goods next fall.
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