Question

Multiply 1.2 and 3.91. Obtain the result as per the rules of significant figures.

(a) 4.692

(b) 4.69

(c) 5

(d) 4.7

I have been asked this question in semester exam.

I would like to ask this question from Uncertainty in Measurement topic in chapter Chemistry Basic Concepts of Chemistry – Class 11

Answer 1

The correct option is (d) 4.7

For explanation I would say: 1.2 x 3.91 = 4.692. Since 1.2 has two significant figures, the result should not have more than two significant figures, thus, it is 4.7. As per the rules of significant figures, the resultant answer should not have more significant figures the number with a less significant figured number.