Here we will show you step-by-step how to calculate 21 plus 15 (21 + 15) using the Long Addition Method. We start by setting up our math problem as follows:
| 2 | 1 | |||||||
| + | 1 | 5 | ||||||
The next step is to add the ones digits together (1 + 5 = 6) like this:
| 2 | 1 | |||||||
| + | 1 | 5 | ||||||
| 6 |
Then in our final step, we add the tens digits together (2 + 1 = 3) like this:
| 2 | 1 | |||||||
| + | 1 | 5 | ||||||
| 3 | 6 |
And that is how you solve 21 plus 15 using the Long Addition Method! The answer is displayed mathematically below:
21 + 15 = 36
Long Addition Calculator
Here you can enter another addition problem for us to explain and solve using the Long Addition Method: