We're told that Linde isn't sure how to subtract 853...
We are told Linde isn't sure
how to subtract 853 minus 283.
Help Linde by choosing an expression
that is the same as 853 minus 283.
So, pause this video and see if you can answer it on your own
before we work through it together.
Alright, now that we look at all the choices,
they all start with 853.
Now, this first choice they subtract out 200
That makes sense because we have 2 hundreds
right over there.
Then they subtract out 50
and then they subtract out 3,
So, the 200 and the 3 make sense.
You can view 853 minus 283
as 853 minus 200,
minus 80, 8 tens right here,
minus 3.
But that's not what they wrote over here.
Instead of putting 80 here, they put a 50.
So we can rule that out.
Here we have 853 minus 20
minus 800 minus 3.
Well, this is a little bit strange
because we don't have 2 tens, we have 2 hundreds
and we don't have 8 hundreds, we have 8 tens,
so this is also incorrect.
Now, it's probably going to be this one,
but let's just make sure we feel comfortable with this.
So, this one has 853 minus 200,
minus 53.
minus 30.
Does that make sense?
Well, let's think about it.
What they're doing,
is they're subtracting out first the 200,
so that this part right over here, so that makes sense.
They're subtracting out first that.
And then they're subtracting out 53
and then subtracting out 30.
Well, that is the same thing
as subtracting out 83,
because subtracting out 83
is the same thing as subtracting out 53 and
and then subtracting 30.
53 plus 30 is 83.
Now, you might be wondering
why would they even do it this way?
What is easier to do in your head?
853 minus 200 is 653.
You take away 53 from that,
so you take away 53 from that,
and you're going to be left with 600.
And then 600 minus 30
— you might recognize that,
you could do 60 tens minus 3 tens —
it's going to be 57 tens,
or you might be able to do it in your head
600 minus 30 is 570.
So, that's why they broke out,
they broke up the 83.
Instead of just breaking it up into 80 and 3,
they broke it up into 53 and 30 to match this 53 over here.
It's easier to work out the result.
Let's do another example.