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To solve this addition problem, follow these steps:
After performing these steps, the final sum is:
Therefore, the sum of 423 and 55 is .
478
\( \begin{aligned} &90 \\ +& \\ &~~9\\ &\underline{\phantom{776}} & \\ \end{aligned} \)
We start from the ones place (rightmost column) because if there's any carrying needed, it flows left to the next column. This prevents errors and keeps our place values organized!
That's normal! When adding 423 + 55, the 55 only has two digits, so imagine a zero in the hundreds place: 423 + 055. Always align by place value, not by length.
Each column's sum goes directly below that column. The ones column sum goes in the ones place of your answer, tens column in tens place, and so on!
Use your finger or a ruler to isolate each column as you work. Start with the rightmost column and move left one column at a time. Take your time!
While possible, it's much harder and more error-prone. Adding right to left is the standard method because it handles carrying naturally. Stick with the proven approach!
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