Indicate the number of significant figures in the following numbers:

  1. 976 ______
  2. 976 000 ______
  3. 96.7 ______
  4. 9.67 ______
  5. 0.00967 ______
  6. 9.6700 ______
  7. 9.067 ______
  8. 30.4 ______
  9. 2700 ______
  10. 5.10 ______
  11. 0.023 ______
  12. 7.0200 ______
  13. 0.04010 ______
  14. 54.000 ______
  15. 34.802 ______
  16. 0.0000565 ______
  17. 4.530 ______
  18. 222 ______
  19. 70 164 ______
  20. 3.00 ______
  21. 2.700 ______
  22. 304 ______
  23. 51.0 ______
  24. 9 ______
  25. 90 ______
  26. 900.0 ______
  27. 0.009 ______
  28. 0.90 ______
  29. 0.090 ______
  30. 909 ______
  31. 0.00881 ______
  32. 0.4900 ______
  33. 0.0224 ______
  34. 0.006007 ______
  35. 0.00005 ______
  36. 0.500 ______
  37. 0.050 ______
  38. 5000 ______
  39. 0.005670 ______
  40. 0.1110 ______
  41. 0.0076009 ______
  42. 670 000 ______
  43. 670 004 ______
  44. 45.908 ______
  45. 0.00872 ______
  46. 54 000 ______
  47. 0.000008 ______
  48. 0.800008 ______
  49. 453.9780 ______
  50. 500 000 000 ______
  51. 24 091 800 ______
  52. 780 ______
  53. 708 ______
  54. 780.0 ______
  55. 780.000 ______
  56. 780.00 ______
  57. 78 000 ______
  58. 500 ______
  59. 0.005 ______
  60. 16 ______

How to +, - , x ,  with significant figures:

  • When adding or subtracting numbers, look at the number of significant digitsafter the decimal in each number to determine how many sig figs you can keep in your answer. You can only keep as many as the least amount of sig figs found in the numbers you are adding or subtracting. Observe:

506.79 (2 sig figs)

32.9006 (4 sig figs) Answer: 539.7

+ 0.002 (1 sig fig) 

539.6926

  • When multiplying or dividing numbers, look at the total number of significant digits in each number to determine how many sig figs you can keep in your answer. You can only keep as many as the least amount of sig figs found in the numbers you are multiplying or dividing. Observe:

34.500 (5 sig figs)

170 (2 sig figs)  Answer: 17 000

x 2.98 (3 sig figs)

17 477.7

Exercises: Solve the following problems on your own paper. Write all of the starting information, show all your work, and box your answers.

  1. 34.92 + .0074 + 503.0
  2. 4.200 x .0078
  3. 13.89  6.8
  4. 5700  14.009
  5. 13.70 - 3.70
  6. 25.25  5
  7. 14 000 - 390.55
  8. 89.09 x 23
  9. 7.6 + 402.91
  10. 0.00881 + 45.908
  11. 7. 200 x 3.56
  12. 222  2
  13. 2.700 - 0.76
  14. 9.600 x 2.5
  15. 87.6 + 4.87 + .0041
  16. 70.164 x 3.33
  17. 546.00  60.667
  18. 5 x 5