Answer :
Final answer:
The correct significant figures after addition or subtraction are based on the number with the least decimal places, so the answers are B) 35.84 and B) 1.024 respectively.
Explanation:
When adding or subtracting numbers, the correct number of significant figures is determined by the number with the least number of decimal places. For multiplication and division, it's determined by the number with the least total amount of significant figures.
For the addition 31.580 + 4.26:
- The number 4.26 has the least number of decimal places, which is two, so the result should be rounded to two decimal places, making the correct answer B) 35.84.
For the subtraction 1.0250 - 0.00063:
- The number 1.0250 has four decimal places, and 0.00063 has five, but since the operation is subtraction, we look at the least number of decimal places after the decimal point that is significant to both, which is three, making the answer B) 1.024 when rounded.
