Answer:
I believe this what you're asking:
To estimate the sum of 3.456 and 8.79, we can round each number to one decimal place, and then add them:
3.456 ≈ 3.5
8.79 ≈ 8.8
So, 3.456 + 8.79 ≈ 3.5 + 8.8 = 12.3
Therefore, we can estimate that the sum of 3.456 and 8.79 is approximately 12.3.
In equation form, this can be written as:
3.456 + 8.79 ≈ 3.5 + 8.8 = 12.3
Hope this helps! I'm sorry if it doesn't. If you need more help, ask me! :]