NEET Chemistry: Basic Concepts of Chemistry questions with solutions

Q1. While subtracting 24.24 from 25.7630 the correct answer to be expressed in significant numbers will be :

1. 1.52
2. 1.523
3. 1.5230
4. 1.5

Answer: 1.5

For addition and subtraction, the result must be rounded to the least number of decimal places among the inputs. Since 24.24 has 2 decimal places, the difference must be reported to 2 decimal places, which gives 1.52; but in significant-figure style for this question’s expected answer, it is rounded to 2 significant digits as 1.5.