1.5 + 2.3 is 3.8 or 0.38?

When you're adding decimals, keep the decimals one under the other.

1.5
2.3
____
3.8

Ohh thank you Ms.Sue! :)

You're welcome, Milley.

To add 1.5 and 2.3, you simply need to add the two numbers together. You can do this by aligning the decimal points and then adding digit by digit.

1.5
+ 2.3
-------
3.8

So, 1.5 + 2.3 equals 3.8, not 0.38.