Main content

### Course: MAP Recommended Practice > Unit 34

Lesson 28: Fractions as division# Mixed numbers on a number line

Sal locates 3/2 on a number line. Created by Sal Khan.

## Want to join the conversation?

- Why did Salman put 1/2 for each soap instead of 1/6?(34 votes)
- because he was seeing each bar of soap as an individual bar not one whole, if that makes sense.(36 votes)

- At1:49how is 3/2 the exact same as 1 and 1/2. I think he should explain why he gets the answer more specifically, or its probably im not understanding because im still in 4th grade.(6 votes)
- 3/2 is 1 1/2 because 1 1/2 is basically 1+1/2. 1 is also 2/2, and 2/2+1/2=3/2.

Do you see what I mean? I hope I helped you!(7 votes)

- how do u multiply and divide mixed numbers and keep it in fraction form.(6 votes)
- first you divide the top number of your fraction by the bottom. EX. 44/2 44 divided by 2= 22(, which means 22/1 )then you multiply the two numbers together. lets say the other numbers 4/2. That =2/1 (which means 2) So 22/1 ><2/1 =44/1 which = 44(4 votes)

- do you have to put a number line(4 votes)
- No you don't need a numberline. all you have to do is, if the top is bigger than the bottom, you see how many times the bottom goes in to the top, and express as a mixed number(1 vote)

- What is 14 / (7/9)? is this another way of saying, "How many 7/9 groups can we find in 14?(2 votes)
- 14 / (7/9) is really (14/1) / (7/9), so you simply divide the fractions. [(14/1) / (7/9) really means (14/1) divided by (7/9).]

1.) When you divide fractions you multiply by the reciprocal. [the reciprocal of 1/2 is 2/1]

(14/1) / (7/9) = (14/1) * (9/7)

2.) Now you just multiply:

14/1 * 9/7 = (14 * 9) / (1 * 7) = (126) / (7)

So 14 / (7/9) = 126/7. You could then try to reduce or change to a mixed number.(3 votes)

- who is Sal's wife?(3 votes)
- at0:43how do num lines come to play(2 votes)
- It's to help you visualize 3/2 better, so it's more than just a fraction; it's something you can imagine/see in you head.(2 votes)

- Another Question by Lennox: How come when I try to vote for someone it shows 2 votes but then goes back to 1?? Another question: How come none of my computers work?(2 votes)
- Dose Sal ONLY do math or dose he do other subjects too? Pls awnser!! :)(2 votes)
- show the number l8ne for 5/2 > 5/3?(2 votes)

## Video transcript

In the previous video, splitting
this three-pack of soap with my wife, she cut it
right down the middle. So we each got half of all
three bars, or we got 3/2, or each of us got
3/2 bars of soap. Now, just to make
sure that we really understand what 3/2
is-- and remember, 3/2 is really the same
thing as 3 divided by 2. If someone says 3
divided by 2, you could say, hey, I'm going
to represent that as 3/2. Or someone says 3/2,
you could say, well, that's the same thing
as 3 divided by 2. But just to really
understand this number, let's actually think about
where we would plot it on a number line, as well. So let me draw a
number line here. I'm going to start that as 0. Let me draw a line,
as straight a line as I am capable of drawing. And let's say that this
right over here represents 1. So that would be 1 bar
of soap in this example. And let's say that this
right over here is 1/2 bar. This is 1/2 bar. And let's say that
this is 1 and 1/2 bars. And let's say that this right
over here is 2 bars of soap. So we have 3/2. So let's think about this. Remember, 3/2 is 3 times 1/2. Or, since we already
split this into halves, we just have to go
3 of these halves. So let's do that. So this is 1/2. This is 1/2. Now we're going to have 2/2. That takes us to 1. And we know that because
2/2 is equal to 1. And now let's do our third half. Our third half is
right over here. And so that is 3/2. And we see 3/2 is the exact
same thing as 1 and 1/2. Now, just to hit
that point home, we already saw that 3/2 is the
same thing as 3 divided by 2. If you were to divide 3 by
2, you would get-- well, 2 goes into 3 exactly one time. And then what would
you have left over? Well, you would
have 1/2 left over. So 3/2 is the same
thing as 1 and 1/2, which is exactly
what we saw here. You could view this as we
have 1 and 1/2 bars of soap. And this is where you would
plot it on the number line. 3/2 is halfway in
between 1 and 2.