Adding means putting numbers together to find the total or sum. Subtracting means taking one number away from another to find the difference.
Addition increases the total, while subtraction decreases it. Both operations help you compare and combine quantities in everyday problems.
When adding whole numbers, line up the digits by place value—ones under ones, tens under tens, and so on. Then add each column starting from the right (ones place) and regroup if needed.
Always check your addition by estimating. For example, 458 is about 460 and 376 is about 380, and 460 + 380 ≈ 840. Your answer, 834, makes sense.
When subtracting, line up the digits by place value and subtract each column starting from the right. If the top digit is smaller than the bottom digit, regroup from the next place to the left.
Check your subtraction by adding the difference and the smaller number. If you get the larger number, your subtraction is correct. Example: 115 + 487 = 602 ✔️
Place value tells you the value of each digit in a number. Correctly lining up digits by place value helps ensure accurate addition and subtraction.
Misaligned digits lead to incorrect sums or differences. Always double-check your alignment before solving.
Addition and subtraction are used to solve real-world problems, such as finding total amounts, comparing differences, or determining how much more or less something is.
Always read word problems carefully to decide whether you need to add (combine amounts) or subtract (find the difference).