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Math Help - [SOLVED] Easy Sig fig question

  1. #1
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    [SOLVED] Easy Sig fig question

    79958.42

    rounded to 3 shouldnt it be like 8.00 or 80.0?
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  2. #2
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    e^(i*pi)'s Avatar
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    Quote Originally Posted by Nismo View Post
    79958.42

    rounded to 3 shouldnt it be like 8.00 or 80.0?
    No, after all think about how far 8 and 80 are from 79958.42

    What you should do is convert to standard form: 7.995842 \times 10^4

    You can then round off the first part to 3sf which is 8.00 but you must bring back the 10^4 to give  8 \times 10^4 = 80000
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  3. #3
    Super Member Quacky's Avatar
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    79958.42
    Remember that with significant figures, 0 counts in the context of a 10 or 100 and so forth, so for example, in 405, the 0 is significant, whereas in 0423, the 0 is not significant.
    Therefore, when rounding this to three significant figures, the answer is 80000, as e^(i*pi) said.
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  4. #4
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    80000 has only one significant figure.

    8.00 \times 10^4 has three significant figures.
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  5. #5
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    thxs everyone for the help.
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