1. The problem is to find a sum of numbers in Excel that results in zero. 2. The formula for summing numbers in Excel is =SUM(range), where range is the cells you want to add. 3. To get a sum of zero, the positive and negative numbers in the range must balance each other out. 4. For example, if you have numbers in cells A1 to A5, you can write =SUM(A1:A5). 5. If the sum is not zero, adjust the numbers so that the total adds up to zero. 6. Remember, zero sum means $$\sum_{i=1}^n x_i = 0$$ where $x_i$ are the numbers in the range. 7. You can use trial and error or solver tools in Excel to find such numbers. 8. In summary, use =SUM(range) and ensure the numbers in the range add up to zero by balancing positives and negatives.