Worked examples comparing improper fractions and mixed numbers. Created by Sal Khan.
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- Is is true that 1 3/7 will always be less than 2 2/4, even though 7 is a larger number than 4?!(0 votes)
- Yes, 1 3/7 will always be less than 2 2/4 and it has nothing to do with the fractions.
1 3/7 has 1 whole unit + a fraction
2 2/4 has 2 whole units + a fraction
2 whole units is always larger than 1, so 2 2/4 is always larger than 2 2/4
If the whole numbers matched, then you would need to compare the 2 fractions. Remember, the denominator tells you the number of pieces that make up a whole unit. So, a 7 in the denominator tells you that fraction has smaller pieces than the one with a 4 in the denominator.
Notice: 2/4 is the same as 1/2. And, 3/7 is smaller than 2/4 because 3 is smaller than half of 7.
Hope this helps.(13 votes)
- when the mixed fraction is the same and you multiply it with a number you get the anwser but in the nuarator is bigger than the denominator(4 votes)
- How do you know if I have the right answer for a problem ?(4 votes)
- How do you simplify improper fractions as mixed numbers?(4 votes)
- You first see how many times the bottom number goes into the top. That is the number part of the mixed number . Then you take the remainder and put over the original numerator to make the fractional part of the mixed number. You put the two parts together and you have your mixed number!(3 votes)
- Is 2 3/7 greater than or less than 1 9/7(2 votes)
- Or you can think of it like this way, 7/7 is equal to 1 whole, and 9 is bigger than 7. So now it's 2 2/7.
2 3/7 is bigger.(2 votes)
- How do you simplify improper fractions as mixed numbers?(2 votes)
- Divide the numerator by the dominator. Take the quotient as the whole number and the remainder as the new numerator. For example, say you have
4 goes into 7 one time with a remainder of 3
The result is 1 3/4
see Khan's explanation here:
- you can make both a mixed number or improper fraction right?(2 votes)
- Yes, you can. For example, a mixed number can be converted into an improper fraction and you can convert an improper fraction into a mixed number.(3 votes)
- can you do a video about just comparing mixed numbers?(3 votes)
- Yes I agree. That would be a good video... I even have math quiz on ADDING and SUBTRACTING mixed numbers and that would be very helpful. There probably is one though and I will try and find it >_<(0 votes)
- Can you turn the mixed number into a improper fraction?(2 votes)
- Yes, an improper fraction is a mixed number.
Let's take an example
Convert 2 2/3 into an improper fraction.
Step 1 |
How many thirds are in 2 wholes?
There are 3 thirds in a whole, and 3 + 3 = 6
So there are 6 thirds in 2 wholes
Step 2 |
How much do we have in the denominator?
Well, in our mixed number, we had a 3 in the denominator, so that will stay the same.
Step 3 |
How much will be in our numerator?
We have 2 from our original fraction, and we add 6 to that. because 6 is equal to our 2 wholes.
2 + 6 = 8
Step 4 |
How much do we have?
We put our 8 over our 3 to get:
So 8/3 is equal to 2 2/3(3 votes)
- How come with the greater and less symbol, in different videos, Sal says different things about how to use them. In this video, he said that you always make the opening face the greater number. But in another video, he said that the opening should face the smaller number. Which one is correct? I might be mixing up something here, but could somebody just tell me the difference, or how I should use the greater and less symbol? Thank you to whoever will answer this question!(2 votes)
- The opening has the greater number!
6 > 3
2 < 7
You can think of it as an alligator that wants to eat the bigger number.(1 vote)
I've got pairs of mixed numbers and improper fractions, and I want to think about which of the two is larger. So 1 and 7/8, 39/10. So you could do this in your head. You could say 10 goes into 39, I'll even write it out, 10 goes into 39 3 times, 3 times 10. And you want to find the largest number of times 10 goes into this without going over. So you couldn't write a 4 over here, because then that would be 40. That would go over 39. 3 times 10 is 30. And then you have a remainder of 9. So you could rewrite this expression right over here. Instead of 39/10 you could write it as 30/10 plus 9/10. And 30/10 is just 3. So this is equal to 3 and 9/10. And you could do that in your head. You could say 10 goes into 39 3 times, and the remainder is 9. You have your 9/10. And that's essentially just doing this in your head. So now we can compare, and we can literally just look at the whole number parts. This is 1 and something, 1 and 7/8, and we're comparing it to essentially 3 and 9/10. 3 and 9/10 is clearly a larger number. We have a 3 out here instead of a 1, so we will write less than. And the way I always remember it is, the opening always faces the larger number. And the point is small. It always points to the smaller number. Now let's do this next one. 4 and 7/8 versus 49/9. So let's convert this to a mixed number. 9 goes into 49 5 times, and 5 times 9 is 45. So the remainder is going to be 4. The remainder is 4, so this is 5 and 4/9. Once again, we can literally just look at the whole number parts. 5 is clearly larger than 4, so once again, less than. Point facing the smaller number, opening facing the larger number. Now 2 and 1/2 versus 11/10. 10 goes into 11 only 1 time. And if you care about the remainder, it's 1. So it's 1 and 1/10. Which is clearly smaller than 2 and 1/2. You just look at the whole number parts. 2 is clearly larger than 1. So we want our opening of our less than or greater than sign to face the larger number. So we would write it like this. And this is greater than, so 2 and 1/2 is greater than 11/10. The little point facing the smaller number. 5 and 4/9 versus 40/7. 7 goes into 40, so let me rewrite this, 7 goes into 40 5 times. And then you're going to have a remainder of 5, because 7 times 5 is 35. You have a remainder of 5 to get to 40. So it's 5 and 5/7. And if that looks like I'm doing some type of voodoo, just remember, I'm really just breaking it up. I'm just really saying that 40/7 is the same thing as 35 plus 5/7. The largest multiple of 7 that is less than this number. And this is the same thing as 35/7 plus 5/7. And then this, 35/7 5. And 5/7 is just 5/7 there. This one is interesting because we have the same whole number out front on our mixed numbers. 5 versus 5. So now we actually do have to pay attention to the fractional part of our mixed number. We essentially have to compare 4/9 to 5/7. And there's a couple of ways to do this. You could get them to have the same denominator. That's probably the easiest way to do it. So you could rewrite-- so what's the least common multiple of 9 and 7? They share no factors, so really the least common multiple is going to be their product. So if we want to rewrite 4/9 we would write 63 in the denominator, that's 9 times 7. If we multiply the denominator by 7 we also have to multiply the numerator by 7. So that will be 28. Now 5/7, we're going to make the denominator 63. We're multiplying the denominator times 9. Then we have to multiply the numerator times 9 as well. 5 times 9 is 45. So here it's easy to see. 45/63 is clearly larger than 28/63. And so we could write this. And because the whole number of parts are the same, and 5/7 is the same thing as 45/63, and 4/9 is the same thing as 28/63, we can write that 5 and 4/9 is less than 40/7. Another way that you could have thought about 4/9 versus 5/7 is you could have said, well, how does 4/9 compare to 4/7? We have the same numerator. The denominator here is larger than the denominator here. But when you have a number in the denominator, the larger it is, the smaller the fraction. The smaller the absolute value of the fraction. So this right over here is a smaller quantity than 4/7. And 4/7 is clearly a smaller quantity than 5/7. So 4/9 is clearly smaller than 5/7, so we would have gotten the same result.