Video Transcript
Subtract eight from 13. Hint: How can subtracting from 10
help you? 13 take away eight equals what.
In this question, we’re being asked
to subtract or take away eight from 13. Sometimes, when we describe a
subtraction like this using words, it can be easy to see the number eight before the
number 13 and think that we might be talking about eight take away 13. Well, this isn’t right at all, and
we need to think carefully about what the words mean. We need to subtract or take away
eight from 13. In other words, we start with 13,
and we take away eight from it. It’s just important to remember
this because sometimes we see the numbers the other way round and we think that this
is the way we need to write our subtraction.
So we need to find the answer to 13
take away eight. But we’re given a hint here. We’re asked how can subtracting
from 10 help you? And underneath this question, we’re
given a little clue to help us. We can see the calculation 13 take
away eight. But we can also see that the number
13 has been split up into 10 and three. Now often, when we split up numbers
like this, we put the larger number first. So you might be expecting it to
look a little bit like this. But, you know, there’s a reason
they’ve been written the other way around. And it’s all to do with how useful
both parts are to us. Remember, we need to take away
eight from this number. Can we take away eight from three
or 10? Well, we know three is too small,
isn’t it? But we can easily and quickly
subtract eight from 10. All we have to do is think of the
number that goes together with eight to make 10.
So in other words, although we
split up 13 into two parts, the most useful part to us at the moment is this 10
here. And that’s why we’ve written it on
the right-hand side so that it’s easier for us to see that we need to take away
eight from it. Now what do we put together with
eight to make 10? We know that eight and another two
make 10. So if we take away eight from the
10 part of our number 13, we’re going to be left with two. But remember, our number 13 isn’t
just made up of 10. It’s also made up of those three
ones. So to find the overall answer,
we’re going to need to take the two that we had left over after the subtraction and
add those three ones. And we know that two plus another
three equals five altogether. And so we can say that 13 take away
eight must be worth five.
So in this question, we needed to
find the answer to 13 subtract eight. And our hint asked us another
question. How can subtracting from 10 help
you? Well, how it can help us is that we
can split up the number 13 into 10 and three. And because it’s much quicker to
take away eight from 10 than from 13, we can work out this subtraction really
quickly and then add the three back on. We know that 10 take away eight is
two. And so 13 take away eight is just
going to be three more than this. 13 take away eight equals five.