Answer: The final answer must have only one decimal place.
Step-by-step explanation:
Significant figures are defined as the figures present in a number that expresses the magnitude of a quantity to a specific degree of accuracy.
We are given:
An addition problem having values (34.530 g + 12.1 g + 1222.34 g)
The rule that is applied for the addition and subtraction is:
The least precise number present after the decimal point determines the number of significant figures in the answer.
For the given problem, the least precise number after the decimal is '1'
Evaluating the value: (34.530 g + 12.1 g + 1222.34 g) = 1268.97 ≈ 1269.0
Hence, the final answer must have only one decimal place.