Question

How many significant figures there are in $3.1205$?

Answer 1

Rules of significant figures

1. Non-zero digits are significant.
2. A zero in between significant digits are significant.
3. In decimal numbers, the zeroes at the end are significant.
4. In a non-decimal number zeroes at the end are not significant.

Explanation

1. In $3.1205$, $3,1,2,5$ are non-zero digits and are significant.
2. The zero is between the significant digits, so the zero is also significant.

Therefore, $3.1205$ has five significant figures.