Video Transcript
Look at how Daniel broke apart a number to help him add. 264 plus 30 equals what? First, add the tens: 60 plus 30 equals what. Then, add the tens to 204 to find 264 plus 30.
In this question, Daniel is adding a multiple of 10, that’s 30, to a three-digit number, 264. Now, the number 264 is made up of two hundreds, six tens, and four ones. And the number that we’re adding, 30, is simply three tens. So when Daniel looks at this calculation, he knows that he only needs to add a number of tens. And so, Daniel has broken apart his number to help him add the tens together.
On one side, he puts the six tens ready for him to add. And the other side is the rest; that’s 204. Now, we’re ready to use Daniel’s method to help find the answer. First, we’re told to add the tens. 60 plus 30 equals what? We can think of 60 plus 30 as being six tens plus three tens. Six plus three equals nine. So we know six tens plus three tens equals nine tens or 90. 60 plus 30 equals 90. So we’ve managed to add the two groups of tens together.
But our number is still broken apart. The final step ask us to add the tens back to 204 to find the overall total of 264 plus 30. In other words, we’re adding 204 plus 90. Our answer is going to have two hundreds, nine tens, and four ones. 204 plus 90 equals 294. And so, we can say that the answer to 264 plus 30 equals 294.
In this question, we were being asked to add a number of tens to a three-digit number. So the way we found the answer was to use Daniel’s method. We broke apart our three-digit number so that we separated out the tens from the rest of the number. To start with, we added the tens together. 60 plus 30 equals 90. And then secondly, we combined our answer of 90 with the rest of the number to find the overall total. The answer to 264 plus 30 equals 294.
