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We're asked to compute 3,060 divided by 36.
We want to figure out how many times does 36-- I don't need
to write it that big.
We need to figure out how many times does 36 go into 3,060.
Now, this is interesting because we're dividing by a
two-digit number, by 36.
We're going to see in this video that the process is the
exact same way.
There's just going to be a little bit more mental
estimation going on, but we'll do it explicitly here, so
hopefully, it won't be too bad.
So we first look at 36, and we say, well, does 36 go into 3?
Well, no.
3 is smaller than 36, so it won't go into 3.
Does 36 go into 30?
No, 30 is still smaller than 36, so it won't go into that.
Does 36 go into 306?
Well, sure.
306 is larger than 36, and if we were to estimate it, 30
would go into 300 ten times, but this is larger than 30, so
it's going to go fewer times.
Maybe it's 9.
I'm not sure.
Let's try it out.
Let me try it out over on the side.
What is 36 times 9?
And this is kind of the art of doing these problems when
you're dividing a two-digit number into something.
So 6 times 9 is 54.
Regroup, or carry the 5.
3 times 9 is 27, plus 5.
27 plus 5 is 32.
So 36 times 9 is 324.
That's still larger than 306, so we're going to have to go
36 less than that, so we're going to
have to do eight times.
So we're going to have to go into it eight times.
And remember, the way I thought about that is I said
my first guess was maybe it goes in nine times, but when I
tried out 36 times 9, that was still larger than 306.
That got me 324.
Eight times should work, because if you take 36 away,
if you only do 8 times 36, that's going to
take us below 300.
342, 136 away from that, or another way, 324 minus 36 is
going to get us below 300.
So let's try this out and just make sure.
8 times 6 is 48.
Put the 8 there; carry the 4.
8 times 3 is 24 plus 4 is 28.
So 8 times 36 is 288 and it fits.
It's less than 306.
9 would've been too much.
It would've been greater than 306, so
now we can just subtract.
So we have 6 minus 8.
We can't just subtract 8 from 6.
We have to do a little bit of regrouping.
Let's get a 10 from the ones place right here, but we can't
borrow anything from here or regroup anything from there,
so let's go to the hundreds place.
Let's take 1 from the hundreds place, and so this will become
a 2, and then this 0 here will become a 10.
Another way to think about it is this is now 10 tens.
We took 100 from there, and we're now
writing 100 as 10 tens.
Or another way to think about it is you borrowed a 1, or you
took a 1, really.
You took a 1 from the hundreds place.
That made it into a 2, and then you put the 1 out in
front of the 0.
That's kind of the process way of thinking about it.
Now, we have this 10 here, and now we can
borrow from this 10.
So let's borrow from this 10.
So this 10 can become a 9.
1 is really taken from it, and then this 6 becomes a 16.
Because if you think about it, this 10 was really 10 tens.
It's in the tens place, so when you put a 10 there, it
really means 10 tens.
So if you take 1 away from it, this is actually now 90, and
we have 10 to give to this 6, and 10 plus 6 is 16, so that's
what we're really doing.
But now we're ready to subtract, so we have 16 minus
8 is 8, 9 minus 8 is 1, and 2 minus 2 is 0.
So we have 18 left over, and now we can bring down this 0
right here.
Bring down that 0.
So how many times does 36 go into 180?
And once again, this is going to be estimation.
It's not going to be six times.
6 times 30 would be 180.
6 times 36 would be too big, because 36 is bigger than 30,
so let's try 5.
Let's see if 5 works.
So let's see.
5 times 6-- and there's a little trial
and error here sometimes.
5 times 6 is 30.
Put the 0; carry the 3.
We don't need that.
That's from last time.
5 times 3 is 15 plus 3 is 18.
It looks like it works out.
You subtract 180 from 180, your get zero,
so we have no remainder.
So we're left with 36 goes in 3,060 eighty-five times.
So this is equal to 85.