Video Transcript
Complete using the symbol for is
less than, is equal to, or is greater than. Five-tenths what seventy
hundredths.
In this question, we’ve got two
values that we need to compare together. And there are a combination of both
digits and words. We’ve got five-tenths and then
there’s seventy hundredths. Now a very easy mistake to make
here would be just to look at the numerals and say to ourselves, “Well, I know that
five is a lot less than 70, so five-tenths must be less than seventy
hundredths.” Now, in a moment we’re going to
compare these values, and it might be the case that the first one is less than the
second, but it’s not because five is less than 70. And that’s because these values are
talking about two different place value units. We’ve got five-tenths and seventy
hundredths.
Let’s sketch a couple of models to
help us see what these values actually mean. We could represent five-tenths by
taking a whole square splitting it into 10 equal parts and then shading five of
them. There are no whole squares, but
there are five-tenths of a square. So we’d write this value as 0.5 if
we were writing it in digits. Our second value is a number of
hundredths. Now, just like all the other
columns, the hundredths place can only fit one digit in. But we’re told that this value is
worth seventy hundredths. If we were to sketch this as a
model again, we’d need our whole square and, this time, to split it into 100 equal
parts. Then we’d need to shade in 70 of
them.
So once again, we’ve shaded in zero
whole squares and we’d write seventy hundredths with a seven in the tenths place and
a zero in the hundredths place. If we drew another model, can you
see that seventy hundredths is actually the same as seven-tenths? That’s why that digit seven goes in
the tenths place. Now we’ve sketched these two
models; we can compare the values quite easily. We can see that five-tenths is less
than seventy hundredths. As we’ve just seen, seventy
hundredths is the same as seven-tenths. And we know that five-tenths must
be less than seven-tenths.
Another way we could find the same
answer is by looking at our place value table and comparing the digits. Both numbers have zero ones, but
our first number has five-tenths and our second number has seven-tenths. So it turns out that five-tenths is
less than seventy hundredths. But it’s not because five is less
than 70. To find the answer, we needed to
work out what five-tenths and also seventy-hundredths were worth. And we use both models and also a
place value table to help compare them. Five-tenths is less than seventy
hundredths. And so the symbol that we need to
use in between these two values to compare them is the one that represents less
than.
