Answer :
The sum of 2.782 and 37.1, when rounded to the correct number of significant figures, is 39.9, which conforms to the one decimal place of the number 37.1.
To add 2.782 and 37.1 while rounding to the correct number of significant figures, you must first perform the addition without rounding. When you add these two numbers together, you get 39.882. However, you must round this result to match the number of decimal places of the least precise measurement, which in this case is 37.1. Since 37.1 has only one decimal place, your final answer should also have one decimal place.
Therefore, after adding, you round 39.882 to 39.9 to adhere to the rules of significant figures.
