Co-Authored By:

**Rules for Numbers WITH a Decimal Point**

- START counting for
**sig**.**figs**. On the FIRST non-zero digit. - STOP counting for
**sig**.**figs**. - Non-zero digits are ALWAYS significant.
- Any zero AFTER the first non-zero digit is STILL significant. The zeroes BEFORE the first non-zero digit are insignificant.??

Moreover, how many sig figs does this number have?

Suppose we **have** the **number** 0.004562 and want 2 **significant figures**. The trailing zeros are placeholders, so we do not count them. Next we round 4562 to 2 digits, leaving us with 0.0046 .

Keeping this in view, what are the 5 Rules for significant figures?

**Significant Figures**

- Annotation category:
- RULES FOR SIGNIFICANT FIGURES.
- All non-zero numbers ARE significant.
- Zeros between two non-zero digits ARE significant.
- Leading zeros are NOT significant.
- Trailing zeros to the right of the decimal ARE significant.
- Trailing zeros in a whole number with the decimal shown ARE significant.

two