5th grade foundations (Eureka Math/EngageNY)
- Multiplying unit fractions and whole numbers
- Multiply unit fractions and whole numbers
- Equivalent fraction and whole number multiplication problems
- Multiply fractions and whole numbers with fraction models
- Equivalent whole number and fraction multiplication expressions
Sal multiplies 1/2 x 5 using repeated addition and fraction models. Created by Sal Khan.
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- If 1/2 x 5 is 5/2 does that mean 5 x 1/2 is the same?(15 votes)
- Yes. When you multiply a fraction or whole number, if the places are interchange, the answers are the same!
#Warning:This doesn't mean the application process is the same!!XD(13 votes)
- 5/6 × 4 is what(7 votes)
- The answer is 20/6, but it is not simplified. You should always simplify fractions if you can. 20/6 can be simplified to 10/3. since 10/3 is an improper fraction, we need to change it to a mixed number. 10 goes inside 3, 3 times and there is one left over. So the answer is 3 1/3. Sorry if this doesn't make sense, I'm only in fifth grade.(18 votes)
- The star (*) is just another way of saying your multiplying so x is also * just with a different shape. =)(9 votes)
- how would you multiply 3 1/4 x 6?(3 votes)
- how do you do mixed fractions * fractions(4 votes)
- For example ,if they ask you (5 1/2) right?than you just calculate it like this(2 times five,which is 10 ,after that,youplus 1 to 10.)I hope it will help ALIVIA S.(5 votes)
- What does it mean by find each product(4 votes)
- This could mean that there's more than 1 multiplication problem present in the question. Which, in this case, you have to find the products of the multiplication given. I hope this helps Eva Medina Whitley!(3 votes)
- so tell me if I'm wrong plz and thanks 9/12 = 3 x 3/12?(4 votes)
- So, like you did in 1/2x5, do you just replace the numerator (1) with the factor so its 5/2?(4 votes)
- No, because if the numerator is not 1 then it would not work and would be a different number. Ex: 4/5 x 4 = 20/5.(1 vote)
- I wonder why don't we add denominators?(3 votes)
- Think about pizzas, if you have 1/2 of a pepperoni and 1/2 of a cheese pizza and put them together, what do you have? 1 full pizza (1/2+1/2=2/2=1) or 1/4 of a pizza?(2 votes)
Let's think about how or what 1/2 times 5 represents. So one way to think about it is that this could be five 1/2's added together. So you could view this as 1/2 plus 1/2 plus 1/2 plus 1/2 plus 1/2, which is the same thing as 1 plus 1 plus 1 plus 1 plus 1, over 2, which is equal to 5/2. The other way to think about this is that you start with 5 things. So let's say, that's 1 thing. Let me copy and paste that so they all look the same. So then let me paste it. So that's 2 things. That's 3 things. That's 4 things. And that's 5 things. So the other way to think about it is you start with 5 things, and you take 1/2 of them. So what would be 1/2 of this? Well, let's see. You have 5 things, so you would get-- 5 divided by 2 would be 2 and 1/2. So you would get this far. Let me make it like this. So you would get this one. You would get this one. And you would get this one. Now, is this the same thing as 5/2? Well, what happens if we divide each of these wholes into halves? So let's do that. So if we just multiplied-- so we just divide each of these into 2. So instead of having 5 wholes, we now have 10 halves. How many of those halves have we filled in? Well, we have filled in 1, 2, 3, 4, 5. So this is also equal to 5/2. So far we just did it thinking about what multiplication actually means. But if you said, well, how did I compute this? Well, the way you could think about it, and multiplying fractions is actually straightforward from that point of view, is as long as you can express both of them as fractions, and 5 we already know is the same thing as 5 ones, so this we can just multiply times 5/1. So now that I've expressed both of them as fractions, I can just multiply the numerator. So 1 times 5 over 2 times 1. And what's that going to be equal to? Well, 1 times 5 is 5. 2 times 1 is 2. So once again, we get 5/2.