Video Transcript
Which number is 468 more than
421?
Let’s sketch a bar model to help us
understand what we need to do to find the answer here. This bar could represent the number
421. Here’s 468 more than 421. And this value here is the number
that is 468 more than 421. It’s the total of both numbers. To find the answer, we need to add
421 and 468 together. We’re going to add the ones, the
tens, and the hundreds digits in these numbers separately. And to help us do this, we can set
out the numbers vertically.
421 is made up of four hundreds,
two tens, and one one. And we’re finding 468 more than
this, which is also made up of four hundreds, but this time, six tens and eight
ones. Let’s start by adding our ones
together. 421 has one one and 468 has eight
ones. One plus eight equals nine ones
altogether. And we can model this answer by
putting our two lots of ones cubes together. One plus eight equals nine. Now, let’s think about our tens
digits. 421 contains a two in the tens
place. That’s where we get the number 20
from. And by finding 468 more than 421,
we need to add another six tens. So what’s two tens plus six
tens?
Well, we know two plus six equals
eight. So two tens plus six tens equals
eight tens or 80. Again, let’s combine our tens rods
this time to show that they make eight tens altogether. Two tens plus six tens equals eight
tens. Finally, it’s time to add our
hundreds digits together. Both numbers have the digit four in
the hundreds place. 400 plus 400 equals 800. And if we combine our hundreds
blocks together, we can see that we have 800 altogether. 400 plus 400 equals 800.
We’ve used column addition. And we’ve also used base ten blocks
to help us find the answer. When we add 421 and 468 together,
we get a number with eight hundreds, eight tens, and nine ones. So we can say that the number that
is 468 more than 421 is 889.
