Final answer:
The correct answer to the equation (4.123 × 0.12) + 24.2 with the correct number of significant figures is 24.70. It is obtained by first rounding the product of 4.123 and 0.12 to two significant figures, and then adding it to 24.2, rounding the result to two significant figures.
Step-by-step explanation:
In order to determine the answer to the equation (4.123 × 0.12) + 24.2 with the correct number of significant figures, we first need to perform the multiplication and then add the result to 24.2. When multiplying 4.123 (which has four significant figures) by 0.12 (which has two significant figures), the least number of significant figures is two, so our product should be rounded to two significant figures. Multiplying these numbers we get 0.49476, which rounds to 0.49 to maintain two significant figures.
Next, we add 0.49 to 24.2. Since 24.2 has three significant figures and our product has two significant figures, we must round the final result to two significant figures because addition follows the least number of decimal places rule. The sum is 24.2 + 0.49 = 24.69, which we round to 24.70 for two significant figures. This matches one of the options provided, so the correct answer is option 3: 24.70.