### Video Transcript

All the robots have been working
hard to make new numbers. Which multiple of 10 have they
added?

In the picture, we can see three
robots, and they seem to have been programmed to do a job involving numbers. We’re told that they’ve been
working hard to make new numbers. Can you see what’s happening in the
picture? Each robot is taking in a
number. It’s then doing something to that
number. But then finally, a new number
comes out of the robot. Now, in the next sentence, we’re
given a clue as to what’s happening here. We’re asked, which multiple of 10
have they added? We can tell a few things from this
sentence. Firstly, we can tell that all the
robots are doing the same thing. The question doesn’t ask us which
multiples of 10. It’s just one multiple. They’re all doing the same
thing.

The next thing we can tell is that
they’re adding a number to the number that goes into them, and also we know what
sort of number they’re adding. Each robot is adding the same
multiple of 10. Now we know that a multiple of 10
is a number in the 10 times table. It’s what we get when we multiply
another number by 10. So the robots could be adding 10,
20, 30, 40, and so on. But which multiple of 10 have they
added? To find out the answer, we need to
look at how the numbers change from the numbers that go in to the numbers that come
out. And we could do this using place
value grids.

With the first robot, the number
that goes in is 22. So that’s two 10s, two ones. And the number that comes out is
62. So that’s six 10s, two ones. This is interesting, isn’t it? We started off with two ones, and
we’ve ended with two ones. No ones have been added at all, but
the number of tens that we have has gone from two to six. Can you see how many tens have been
added by this robot? Two plus four more 10s makes six
10s, don’t they? And as we say, the robot hasn’t
added any ones at all. And if we’ve got the right answer
here, we’d hope that the other two robots have done exactly the same thing.

Our second robot has taken the
number 14, which is one 10, four ones. And we can see that the new number
it’s made is 54, five 10s, four ones. Once again, the number of ones
hasn’t changed, but we’ve got four more 10s. The multiple of 10 that these
robots are adding is 40, isn’t it? And if we just check the last
robot, if we have six 10s or 60 and we add four 10s or 40, we’re going to end up
with 10 10s, which is the same as 100. By adding a multiple of 10 each
time, we notice that the number of ones doesn’t change. The number of tens, however,
does. And these robots have increased the
number of tens by four. And that’s how we know the multiple
of 10 that each robot has added is 40.