Main content

### Course: Class 4 > Unit 3

Lesson 4: Multi digit division (no remainders)# Long division: 280÷5

Learn to divide 280÷5 with long division. The answer wil not have a remainder. Created by Sal Khan.

## Want to join the conversation?

- if 280 divided by 5 what is 2800 divided by 5(3 votes)
- Just add a zero to the end of the answer to 280/5 (the '/' means divide).(18 votes)

- thank you but I still dont get long division(3 votes)
- If you understand this, you understand place value.

Q)3618/9

Correct: 3618/9 = 402 because

(3600+18)/9 = 3600/9 + 18/9 =400+2 = 402.

Wrong: 3618/9 = 42 because 36/9 = 4 and 18/9 =2.

If you multiply 42*9 we get 288.

If you multiply 402*9 =3618

When in confusion, distribute the number in to parts that are divisible by the divisor.

In this example we distributed the parts which are divisible by 9.

Copy and paste the link in url to see in visual.

https://drive.google.com/open?id=1wa1TFXf99pnjgdpL3BZCLNLbmRJ8CPK8(12 votes)

- this creator that created khan khadmey is the best(3 votes)
- His name is Salman Khan (Sal for short)(3 votes)

- NYCs population is 8,537,673. One out of every 21 residents is a millionaire. To find out how many millionaires live in NYC would I first divide the population by 21 and then what?(2 votes)
- If you think about it the answer of how many millionaires in NYC is 406,503. Use the steps in the video.(2 votes)

- Is this standard algorithm but being didvided by(3 votes)
- did you know that you can call it dad mom sister brother dad for divide ,mom for multiply sister for subtract, and brother for bring down.(3 votes)
- My child has gotten better at long divisi(3 votes)
- This video goes by very fast and is extremely confusing. If you want to be able to really learn long division step by step, you're better off going to youtube.(2 votes)
- This is really frustrating what is 4÷3872 and the rest?(2 votes)
- we can division except zero(2 votes)

## Video transcript

Let's tackle a slightly more
interesting division problem. So we're going to take
280 and divide it by 5. And I encourage you
to pause this video and try to apply the
technique that we've seen in a previous video
to try to figure out what 280 divided by 5 is. So let's have our go at it. So we could rewrite this. We've already seen this
as 280 divided by 5. So the first question
we can ask ourselves is, how many times
does 5 go into 2? Well, 5 doesn't
go into 2 at all. It goes 0 times. 0 times 5 is 0. And then we subtract. 2 minus 0 is 2. And now, we can bring
down the next digit, which, in this case, is an 8. And so we can ask
ourselves, how many times does 5 go into 28
without going over it? So we could think, well,
let's see 5 times 5 is 25. 5 times 6 is 30. So 5 times 6 would go over 28. So we want to go
back to 5 times 5. So 5 goes into 28 5 times. 5 times 5 is 25. And you subtract. 28 minus 25 is 3. And now, let's bring
down the next digit. In this case, the digit is a 0. So how many times
does 5 go into 30? Well, it goes exactly 6 times. We've already talked about that. 6 times 5 is 30. We subtract. And we have nothing left over. So we just figured out that 280
divided by 5 is equal to 56. Now, why did this work? Well, the first way to
think about it, this was actually 200. And we were thinking
about, do we put anything in the
hundreds place here? So one way of thinking about
it, how many hundreds of times does 5 go into 200? And it doesn't go
any multiples of 100. And if that's a
little confusing, don't worry too much about it. But I want you to
really think deeply about the place notation. But then we were able
to, again, extend it to instead of just
200 but then 280. This 28 right over here,
if you think about it, this 2 is in the hundreds place. This 8 is in the tens place. So this is really
representing 280. And we said, how many tens
of times does 5 go into 280? Well, it goes 5 tens
times, or it goes 50 times. 50 times 5 is 250. When you subtract 250
from 280, you've got 30. And there were no other
things in the ones place here. So we just have to
figure out how many times does 5 go into 30. So hopefully, that
gives you a sense of what's actually happening
behind this little process. It's not just magic. We're really just keeping
track of place value here. The other thing I
want to show you is that we didn't necessarily
have to write this 0 here. Another way of
computing it, we could have said 280 divided by 5. And we could've said, how
many times does 5 go into 2? Well, it doesn't go any times. So let's just think
about 5 going into 28. Well, 5 goes into 28 5 times. 5 times 5 is 25. Subtract. 28 minus 25 is 3. Bring down the 0. 5 goes into 30 six times. 6 times 5 is 30. And we have nothing left over. And again, what
we're really saying is that 5 doesn't go into
200 any hundreds of times. If this was a 500,
you could say, hey, it's going to go
in it 100 times. But instead, we go, well,
what about 5 going into 280? Well, it goes 50 times. 50 times 5 is 250. 280 minus 250 is 30. 5 goes into 30 six times. So hopefully, that makes
a little bit of sense.