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Rule for Using Sig Figs in Math:. The result of your calculations can never be more precise than your LEAST precise number!. Example. You may know very precisely that the volume of your bucket is 401234.2 ml , but if you have a very uncertain number of drops/ml (24 drops/ml)…
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Rule for Using Sig Figs in Math: The result of your calculations can never be more precise than your LEAST precise number!
Example • You may know very precisely that the volume of your bucket is 401234.2 ml , but if you have a very uncertain number of drops/ml (24 drops/ml)… 24 drops/ml x 401234.2 ml = 9629620.8 drops? -or- 9600000 drops?
Multiplication/Division • Round to the same number of places as the number with the least sig figs. • 12 x 230.1 = 2761.2 (calculator) = 2800 • 0.00325 / .120 = 0.0270833333333 (calc) = 0.0271 = 70.65 (calc) = 70
Addition and Subtraction • Round to the last sig fig in the most uncertain number. 9.12 + 4.3 + 6.01 = ? 19.43 (calc) 9.12 4.3 + 6.01 19.4
0.11001 - 2.12 - 12 = ? -14.00999 (calc) 0.11001 2.12 -12______ -14
1884 kg + 0.94 kg + 1.0 kg + 9.778 kg = 1896 kg
2104.1 m – 463.09 m = 1641.0 m
2.326 hrs – 0.10408 hrs = 2.222 hrs
10.19 m x 0.013 m = 0.13 m2
140.01 cm x 26.042 cm x 0.0159 cm = 58.0 cm
80.23 m ÷ 2.4 s = 33 m/s
4.301 kg ÷ 1.9 cm3 = 2.3 kg/cm3
What if Multiplication/Division and Addition/Subtraction are combined? Do it in steps, according to the order of operations…
(2.39 m – 0.2 m)12.43 s = 2.2 m 12.43 s = 0.18 m/s
2.00 m – 0.500(0 + 3.0 m/s)(3 s) = 2.00 m – 0.500(3.0 m/s)(3s) = 2.00 m – 5 m = -3 m
0.37 m – 1.22 m – (4 m/s)(3.0020 s)0.5000 x (1.0021s)2 = 0.37m – 1.22m – 10m 0.5000 x (1.0021s)2 = _____- 10 m______ 0.5000 x (1.0021s)2 = - 20 m/s2