Video Transcript
There are three groups. I can skip count in fours. There are 12 dots in total. How many are there in five groups
of four?
Now, that speech bubble at the top
is here to help us. So before we start looking at the
problem, let’s go back and think about what it’s trying to tell us. Firstly, there are three groups and
these are represented in the diagram by the three squares. And inside each square, there’s an
equal number of dots. And that’s why the number four is
mentioned because each group contains four dots.
Now, if we were asked to find the
total number of dots, when we first learn to count, we might start off by counting
every single dot individually: one, two, three, four, five, six, seven, and so
on. But as we get more confident with
math, we can understand that it’s quicker to skip count. And in this case, we skip counting
in fours.
And skip counting means instead of
saying every single number, we jump in fours instead. When we first learn how to skip
count, a good way to do this is to say all the numbers, but just to whisper all the
numbers in between the fours. So let’s do that: one, two, three,
four, five, six, seven, eight, nine, 10, 11, 12.
Did you notice the three numbers
that we said, four, eight, 12? We can skip count in fours: four,
eight, 12. There are three groups we can skip
count in fours. There are 12 dots in total: four,
eight, 12.
Let’s have a look at our
problem. How many are there in five groups
of four?
We can start off by thinking of our
five groups. And they’re all equal groups
because we’re told that we need five groups of four. How many are there altogether? Well, again, when we first learn to
count, we could count each dot individually. But now we know a quicker way to
find the answer.
Here’s our number line. This time instead of whispering,
because we’re getting more confident, let’s just say the numbers as we skip count in
fours: four, eight, 12, 16, and 20. How many are there in five groups
of four? Four, eight, 12, 16, 20.
Let’s practice our skip counting
skills with another problem.
How many are there in seven groups
of three?
So we know what seven groups of
three look like. There are seven groups and they’re
equal groups because each one has three dots in it, seven groups of three. So shall we count every single
dot? One, two, three. Now, we know a much quicker way; we
can skip count.
Remember that in this question,
we’ll not skip counting in four. We need to skip count in groups of
three: three, six, nine, 12, 15, 18, and 21. And so we found a quick way of
counting. And as we get more confident, we
don’t even have to use a number line.
How many are there in seven groups
of three? Three, six, nine, 12, 15, 18,
21.