Rules for Significant Digits Rules Significant or not

Rules for Significant Digits Rules Significant or not significant? Digits 1 -9 Significant Zeros between two significant digits Significant Zeros to the right of the decimal place and right of the significant digit Significant Zeros used to the right of the decimal place and the left of the significant digit (placeholders) NOT Zeros used to the right of the significant digit but left NOT of the decimal point are not significant

Example of the rules of sig figs EXAMPLES # OF SIG. DIG. COMMENT 4534 kg 4 All non-zero digits are always significant. 2007 L 4 Zeros between 2 sig. dig. are significant. 5. 00 3 Additional zeros to the right of decimal and a sig. dig. are significant. 0. 007 1 Placeholders are not sig. 700(. ) 1 Left of sig fig but right of decimal point

Multiplication and Division • RULE: When multiplying or dividing, your answer may only show as many significant digits as the multiplied or divided measurement showing the least number of significant digits. 22. 37 cm x 3. 10 cm x 85. 75 cm = 5946. 50525 cm 3 = 5. 95 x 103 cm 3 (or 5950 cm 3)

Adding and Subtracting • RULE: When adding or subtracting your answer can only show as many decimal places as the measurement having the fewest number of decimal places. 3. 76 g + 14. 83 g + 2. 1 g = 20. 69 g = 2. 7 g

Finally…combining all together • Use PEMDAS rules, and break down sig figs one equation at a time • Ex –(3. 6 + 3. 72) * (4. 58 / 6. 214) = (7. 32) * (. 737045) = (7. 3) * (0. 737) – 5. 38 5. 4