To determine what numbers are significant and which aren't, use the following rules:
The zero to the left of a decimal value less than 1 is not significant.
All trailing zeros that are placeholders are not significant.
Zeros between non-zero numbers are significant.
All non-zero numbers are significant.
If a number has more numbers than the desired number of significant digits, the number is rounded. For example, 432,500 is 433,000 to 3 significant digits (using half up (regular) rounding).
Zeros at the end of numbers that are not significant but are not removed, as removing them would affect the value of the number. In the above example, we cannot remove 000 in 433,000 unless changing the number into scientific notation.
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