Question

Write down number of significant figures in the following: 1) 25.42 ii) 0.004672 iii) 35.320 ​

Answer 1

Answer:

(i) 2

(ii) 4

(iii) 3

Explanation:

We know that numbers are often rounded to avoid reporting insignificant figures.

(i)The First rule is that all non-zero digits are considered as significant: 1, 2, 3, 4…….

(ii)Then the second rule is Zeros between non-zero digits are also considered as significant: 102, 200005, 25020…..

(iii)Now, the third rule can be given as: Leading zeros are never significant: 0.02, 001.887, 0.000515.

(iv)Fourth and the most significant rule is that in a number with or without a decimal point, trailing zeros which are on the right of the last non-zero digit are significant if they are justified by the precision of their derivation: 252,0000; 5.02121000; 6.900; 42.697800

On basis of these rules, we can say that

1. 25.42 have 2 significant figures.
2. 0.004672 have 4 significant figures, as zeroes before the non-zero numbers are considered insignificant.
3. 35.320 have 3 significant figures.

Thank you