Final answer:
The correct answer to the arithmetic operation (4.033 + 88.1) / (4.3 × 0.31) with the appropriate number of significant figures is b. 70.0.
Step-by-step explanation:
To find the answer for the given arithmetic operation with the correct number of significant figures, we must follow the rules of addition, subtraction, multiplication, and division for significant figures.
First, we perform the addition in the numerator: 4.033 + 88.1 = 92.133. Since 88.1 has the least number of decimal places (1), our result should also have 1 decimal place: 92.1.
Next, we carry out the multiplication in the denominator: 4.3 × 0.31. Here, 4.3 has 2 significant figures and 0.31 has 2 significant figures as well, so the result should have 2 significant figures. However, because multiplication is not limited by the decimal places but by the total number of significant figures, we perform the multiplication first and then round it to 2 significant figures: 4.3 × 0.31 = 1.333, rounded to 1.3 (since 1.3 has 2 significant figures and is the rounded form of 1.333).
Finally, we divide the numbers: 92.1 / 1.3 = 70.846153, which should be rounded to the least number of significant figures in the numerator or denominator. Because we rounded the denominator to 2 significant figures, the final result should also have 2 significant figures: 70 (as the trailing zero is necessary to show that we have 2 significant figures).
Therefore, the correct choice is b. 70.0, as this answer has the appropriate number of significant figures.