How many significant figures are in the number 0.00321?

Answer 1

0.021 contains two significant figures. This indicates that an approximation has been made and the full number was, for example 0.0212.

Note : This should not be confused with necessary and unnecessary zeros. The 0 immediately after the decimal point is a necessary zero. The zero in front of the decimal point is an unnecessary zero but is usually left in place in the absence of a whole number.

Answer 2

Chop off any zeros on the left. How many digits are left?

3. There are 3 significant figures.

Note that you should not chop off digits on the right - 0.00121 is different from 0.001210: 0.001210 is specified to 4 significant figures (if the fourth figure weren't significant, it would have been left out!).

Answer 3

3 sig figs: 1, 2, 1

Answer 4

3 of them.

Answer 5

Three