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Significant Figures - Scientific Notation

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Need to calculate the average of the following two figures, and be sure to keep significant figures.

19.5 + 20.40 = 39.9

39.9 /2 = 19.95

If the answer is 19.95, what is the answer using significant figures only?

Can the answer containing significant figures be put into scientific notation?

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Solution Preview

19.5 ==> 3 significant figures

20.40 ==> 4 significant figures

19.5 + 20.40 = (3 significant figures) = 39.9

39.9 ==> 3 significant figures

[ 39.9/2 ] =(3 significant figures) = 20.0 ==> the ...

Solution Summary

The answer is given step-by-step with explanation. The scientific notation significant figures are determined.

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