Video Transcript
How much longer is the bigger
pencil than the smaller one?
Our picture shows two pencils, a
red one and a yellow one. Now, if we look at how these
pencils have been lined up, we can see that the pointed end, which is the end that
we write with, are both level with each other. This makes it easier for us to
measure and also to see which pencil is longer. If we look at the other end, which
is the end with the rubber, we can see some dotted lines which clearly show us the
red pencil is the bigger.
But our question wants us to find
the difference between these two lengths because it asked us, how much longer is the
bigger pencil than the smaller one? And to find out this, the first
thing we’re going to have to do is to measure these pencils.
Let’s start with the red one. We can see that the pointed end of
the pencil is level with the number zero on our ruler. And if we look carefully, we can
see the letters cm. Which means that we’re measuring in
centimeters. And the red pencil goes all the way
from zero to the number 19 on our ruler. It’s 19 centimeters long. Now, let’s measure our yellow
pencil. Again, we’re starting measuring
from zero. But this time, the pencil only goes
as far as the number 16. It’s 16 centimeters long.
Now, we can use what we’ve found to
answer the question. How much longer is 19 centimeters
than 16 centimeters? One way of finding the answer is to
use our ruler as a sort of number track or number line. All we have to do is to count how
many centimeters there are in between our two lengths. To get from 19 to 16, we can count
one, two, three centimeters. It looks like the bigger pencil is
three centimeters longer than the smaller one.
Another way we can find the
difference is to subtract. So, we start with the longer
length, which is 19, and we’re going to take away 16. So, we’re going to take away one,
two, three, four, five, six, seven, eight, nine, 10, 11, 12, 13, 14, 15, 16. We’re left with three.
We found the same answer in two
different ways. The bigger pencil is three
centimeters longer than the smaller one.