Video Transcript
Compare the numbers on the
cards. Which symbol is missing? 84 what 48. Hint: use the number line.
At the very bottom of this problem,
we’re given three symbols. We’ll go through what each one
means later on. We use these symbols to compare
numbers together. And we’re given two two-digit
numbers. We need to decide which of the
three symbols goes in between these numbers. The two numbers that we need to
compare on the cards are 84 and 48. We need to think about whether 84
is less than 48, whether it’s greater than 48, or whether the two numbers are the
same.
Now, there are different ways we
could do this. But in this particular question,
we’re told how to find the answer. We’re given a hint and it says, use
the number line. Now, when we’re given a hint in a
question, it usually means “do this.” So let’s use the number line to
help us. I can’t see the number 84 on this
number line, can you? Where do you think it belongs? Well, I can see the number 80
here. The number 90 comes after this, and
we know that 84 is in between 80 and 90. Can you see this notch halfway
between 80 and 90? Because it’s halfway, we know that
it stands for 85. And 84 comes just before 85.
So let’s draw an arrow just before
this middle notch. And we’ll label it 84 just to
remind us what we’re labeling. Now, let’s label our second
number. Where’s the number 48 on the number
line? Can you see the number 40? And we can see the number 50 after
it. The halfway point in between must
be 45. And we know that 48 comes after
45. It’s nearly 50. So let’s draw an arrow just before
50, and we’ll label it 48. This is a good question, isn’t it,
because it’s already got us thinking about number lines and we haven’t even started
comparing these two numbers yet.
But now that we’ve labeled our
numbers, we can compare them. Where’s the number 84 compared to
48? We can see that it’s in this
direction. It’s to the right of the number
48. We know as we move to the right
along this number line, we go from smaller to larger. We can see this if we look at the
numbers as a label, can’t we? We start at zero, and as we move to
the right, we go on to 10, 20, 30, 40, and so on. These numbers are getting bigger
and bigger. So because 84 is to the right of
48, it’s a larger number. 84 is greater than 48.
Now, we just need to choose the
correct symbol to use in between the two numbers. Which symbol means is greater
than? Well, we know that this symbol
means is equal to or is the same as. So let’s cross out this symbol. We know this isn’t right. Now, we’re left with these two
symbols that look a little bit like arrows. It’s often easy to get
confused. Which one means is greater
than? The way we can remember which is
which is that the narrow part of each arrow always points to a smaller number, the
wider part of each symbol always points towards the larger number. And the other thing to remember is
that we always read from left to right.
So if we look at this first symbol,
we can see that we start with a smaller number, end with a larger number. The smaller number is less than the
larger number. So this symbol means is less
than. And if we read the second symbol
from left to right, we can see that we start with a larger number. The larger number is greater than
the smaller number, so this symbol means is greater than. Hopefully, we’ve reminded ourselves
which symbol we need to use. 84 is to the right of the number 48
on our number line. And we know that all numbers to the
right of another number are larger numbers. The correct symbol to use in
between 84 and 48 is the one that represents is greater than. 84 is greater than 48.
