Copy written by Professor M.V. Walker Waugh

Name_____________________

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Section________________

Date_______________

Waugh Sheet #1

Addition and Subtraction with Significant Figures

Rules:

1.      All numbers must be in the same power of 10.

2.      Line up the decimal points.

3.      Report your answer with the same number of DIGITS AFTER THE DECIMAL POINT as the number in the operation that has the LEAST number of DIGITS AFTER THE DECIMAL POINT.

4.      Perform on paper without calculator. You are smarter than the calculator!

 Example #1:  2.80 cm  + 17.109 cm = ___?___                                                           2.80   cm   (2 DIGITS AFTER THE DECIMAL PT)                                                       17.109 cm   (3 DIGITS AFTER THE DECIMAL PT)                                                       19.909 cm   (You must report only 2 DIGITS AFTER THE                                                                                    DECIMAL POINT)                                                 Reported Answer = 19.91 cm

 Example #2:  7.189 x 105 g – 8.9 x 104 g = ___?___ (Make sure to change both numbers to 105 or 104, before you attempt to solve this problem.)                                                                                                7.189 x 105 g                                                  –  0.89   x 105 g                                                      6.299 x 105 g                                                   Reported Answer = 6.30 x 105 g

Directions:  Perform the following operations and report your answers in SCIENTIFIC NOTATION.  Show all work NEATLY ON A SEPARATE SHEET OF PAPER that is attached with a staple or your answer is VOID.  Place your answer in the space provided below.

1.      1, 025 m  -  28.9 m  =  ___________________

2.      505 kg + 450.25 kg = ___________________

3.      0.15 cm + 1.15 cm + 2.051 cm = ___________________

4.      9.28 x 103 fg + 8.72 x 102 fg = ___________________

5.      0.55 cm + 36.15 cm + 17.3 cm = ___________________

6.      27.55 x 10-9 g – 15.545 x 10-7 g = ___________________

7.      7.397 x 108 ng + 8.1094 x 109 ng = ___________________

8.      9.999 x 103 pL – 8.985 x 102 pL=___________________

9.      9.61 x 105 mL + 5 x 104 mL = ___________________

10.  22.10 mL – 10.5 mL = ___________________