Final answer:
When adding decimals, you always line up the decimal points and drop the decimal straight down to ensure correct alignment of place values.
Step-by-step explanation:
When adding decimals, you ALWAYS line up your decimal points, use place holders if necessary, and drop the decimal straight down. This is important because it ensures that the place values are aligned correctly. Let's take an example:
2.1 + 0.35 = 2.15
Here, we lined up the decimal points, used a placeholder (0) for the tenths place in 0.35, and dropped the decimal straight down to get the correct sum, 2.15.
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