The rules for identifying significant figures when writing or interpreting numbers are as follows:
All non-zero digits are considered significant. For example, 91 has two significant figures (9 and 1), while 123.45 has five significant figures (1, 2, 3, 4 and 5).
Zeros appearing anywhere between two non-zero digits are significant. Example: 101.1203 has seven significant figures: 1, 0, 1, 1, 2, 0 and 3.
Leading zeros are not significant. For example, 0.00052 has two significant figures: 5 and 2.
Trailing zeros in a number containing a decimal point are significant. For example, 12.2300 has six significant figures: 1, 2, 2, 3, 0 and 0. The number 0.000122300 still has only six significant figures (the zeros before the 1 are not significant). In addition, 120.00 has five significant figures since it has three trailing zeros.
Say 251.206 to 4 significant figures = 251.2 Say 251.274 to 4 significant figures = 251.3 Say 25461.214 to 2 significant figures = 25000
When multiplying numbers, count the number of significant figures in each number being multiplied. The result should have the same number of significant figures as the number with the fewest significant figures.
4 significant figures.
To find a number to two significant figures or any amount of significant figures you look at one plus the amount of asked figures, in this case the third significant figure, and if it is 5 or greater increase the asked amount of significant figures by one. If it is 4 or less make no changes to your number. Finally report the calculated number with the asked amount of significant figures.
There are 4 significant figures in 0.0032. Seems to be only 2 significant figures in this number.
There are 3 significant figures in 94.2.
3 significant figures.
4 significant figures.
5 significant figures.
4 significant figures.
3 significant figures.
There are four significant figures in 0.1111.