To effectively compare two decimal numbers, the first step is to align their decimal points vertically. This alignment ensures that each digit occupies the correct place value column, facilitating an accurate comparison.

For instance, let’s compare the decimals $3.456$ and $3.462$. We can write them as follows:

Beginning with the leftmost column (the units place), we compare the digits. In this case, both numbers have the digit ‘3’, so we proceed to the next column to the right (the tenths place), where we also find ‘4’ in both numbers. Next, we examine the hundredths place, where again both numbers contain ‘5’. Finally, in the thousandths place, we observe that $6$ (from $3.462$) is greater than $5$ (from $3.456$). Thus, we conclude that $3.462$ is greater than $3.456$.

If one number has fewer digits than the other, you can append zeros to the end of the shorter number to simplify the comparison. For example, when comparing $2.5$ and $2.50$, we can express them as:

This representation shows that the two numbers are identical, confirming that $2.5$ is equal to $2.50$.

In summary, the essential strategy is to compare each corresponding digit in the same place value, starting from the leftmost digit and progressing rightward until a difference is detected. This method guarantees an accurate comparison of any two decimal numbers.