1. Rules for Significant Figures
K. Culbertson

2. 459
How many digits are significant? 3

3. 2.1
How many digits are significant? 2

4. .87992
How many digits are significant? 5

5. Rule #1
All digits 1-9 are significant

6. 104
How many digits are significant? 3

7. 1.0402
How many digits are significant? 5

8. 10.508
How many digits are significant? 5

9. 100001
How many digits are significant? 6

10. Rule #2
Zeros in between 1-9 digits are significant

11. 1.800
How many digits are significant? 3

12. 8.060
How many digits are significant? 4

13. 100
How many digits are significant? 1

14. 100.
How many digits are significant? 3

15. 100.0
How many digits are significant? 4

16. Rule #3
Trailing zeros are significant when there is a decimal point

17. 0.0090
How many digits are significant? 2

18.
How many digits are significant? 4

19. 0.470
How many digits are significant? 3

20. Rule #4
Place holding zeros are NOT significant

21. End Clickers -Pass to the Center-

22. Practice! Complete the Practice Worksheet
Be prepared to explain how to arrived at your answer!

23. Sig Fig Race There are four rounds There are 8 people in each group
Each person has a number card (numbers 1-8)
Identify the number of sig figs in the problem set for each round
Use your number cards to organize yourself in the order of the answers for the round
Example Round: Answers = 2,5,6,8,1,3,4,7 2 5 6 8 3 4 7

24. Calculating with Significant Figures

25. Multiplication & Division
3 x 2.0 x 1.00 = x 2.0 x 1.00 = x 2.00 x 1.00 = / 2 / 1 = / 2.0 / 1.0 = / 2.00 / 1.00 = 5.00

26. Multiplication & Division
3 x 2.0 x 1.00 = x 2.0 x 1.00 = x 2.00 x 1.00 = / 2 / 1 = / 2.0 / 1.0 = / 2.00 / 1.00 = 5.00 The answer can contain no more significant figures than the least accurate measurement.

27. Addition & Subtraction
= = = = – 0.5 – 0.42 = – 5.00 – 0.42 = 3.28

28. Addition & Subtraction
= = = = – 0.5 – 0.42 = – 5.00 – 0.42 = 3.28 The answer can contain no more decimal places than the least accurate measurement.