Arithmetic (all content)
Multiplying unit fractions and whole numbers
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?(26 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(26 votes)
- 5/6 × 4 is what(10 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.(30 votes)
- The star (*) is just another way of saying your multiplying so x is also * just with a different shape. =)(18 votes)
- how would you multiply 3 1/4 x 6?(9 votes)
- Try converting 3 1/4 to an improper fraction, that should make it a lot easier(12 votes)
- how do you do mixed fractions * fractions(8 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.(10 votes)
- What does it mean by find each product(8 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!(8 votes)
- hey~ mind if i get thitrty likes?~(10 votes)
- so tell me if I'm wrong plz and thanks 9/12 = 3 x 3/12?(6 votes)
- U are right. 9/12 does equal 3x3/12 because 3x3 is 9.(5 votes)
- when adding them together to get 5/2 why are the 1's added but yet the 2's stay as 2 and not 10?(7 votes)
- I love him
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.