Final answer:
In significant figure rules for addition, the result is rounded to the least number of decimal places in the numbers being added. For the calculation 7.939 + 6.26 + 11.1 = 25.299, the answer should be 25.3 as 11.1 has the fewest decimal places.
Step-by-step explanation:
When dealing with significant figures (Sig Figs) in addition and subtraction problems, the rule is that the final result should be rounded to have the same number of decimal places as the number with the fewest digits to the right of the decimal point.
Given the problem 7.939 + 6.26 + 11.1 = 25.299, we identify that 11.1 has the fewest decimal places, specifically one decimal place. Therefore, we must round our calculated sum, 25.299, to one decimal place. The correct answer, which is rounded to one decimal place, would be 25.3.
The final answer, consistent with the significant figure rules for addition, is 25.3.