Video Transcript
Olivia has broken apart a number to help her add. 413 plus five equals what? Add the ones. Three plus five equals what? Add the ones to 410 to find the total. 413 plus five equals what?
In this problem, Olivia is working out the answer to 413 plus five. And by the way that the question’s been written, we can see that she does this in three different steps. And we can go through these steps as we answer the question.
In step one, Olivia breaks apart a number. Let’s think about why she might do this. We know that our starting number, 413, is made up of four hundreds, one ten, and three ones. And the number she needs to add to this is five, which is represented by five ones. There are no hundreds and no tens in five, simply five ones.
So because Olivia is only adding a number of ones to her three-digit number, she knows she can just look at the ones digit. And so she breaks apart her number so that the ones are separated. Let’s do that now. Here we go. This is exactly what Olivia’s done with her part whole diagram. On one side, she separated out the three ones. And on the other side, she has what’s left, 410. She breaks apart the number to help her add the ones and just to concentrate on the ones without worrying about the hundreds and tens. That was step one.
Now she moves on to step two. And we’re told to add the ones. Three plus five equals what? The three in this calculation is talking about the part of 413, the ones digit that we need to add. And the five is obviously the five ones that we need to add to it. So what’s the answer? Three plus five equals eight. So we can complete the calculation that we’re being asked. Because we know three ones plus five ones equals eight ones, we can use this to help us find the answer to the addition.
Olivia needs to combine her two parts back together again to find the overall answer. This is what step three asks us to do. Remember, she has 410, which is the part she separated in the first place. And she also has her new ones total, eight ones. So we need to add the ones to 410 to find the total. Let’s combine the two parts back together again. All done.
In our new number, we have four hundreds, one ten, and then those eight ones that we were talking about. Our new number is worth 418. And this is the total of the addition that Olivia was trying to find. 413 plus five equals 418.
Because we were adding a number of ones to a three-digit number, the first thing we did was to break up that three-digit number to separate out the ones. To start with, we added the ones. Three plus five equals eight. And then we added the ones to 410 to find the total. 410 plus eight equals 418. So we knew this was the answer to our addition. 413 plus five equals 418.
