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Evaluate the Following Using logarithm

Table
1) 5.25 Multiplied by 23.73

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4 answers

  1. I don't know it

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  2. log(5.25) + log(23.73) = log(5.25 * 23.73)

    find the logs and add them ... this is the log of the answer

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  3. I doubt if many people will read this, but it was fun doing it...

    My goodness, I recall teaching this over 50 years ago.
    You mean to tell me, this is still on your curriculum???

    Dilemma :

    If your text still has tables in the back of the book, it must be over
    25 years old, and it is time to get a new text from your school board.

    If you don't have tables, then you must use a calculator.
    If your calculator can do logs, then surely it can do basic multiplication.

    after about 1990, I would use this type of question only as a "historical
    novelty" in the introduction to logarithms.

    Here are the actual steps needed to do it the old way:
    let x = 5.25*23.73
    log x = log 5.25 + log 23.73

    log 5.25 = .7202 , most tables only had 4 digits
    log 23.73
    = log (2.373 * 10^1)
    = .3753 + 1 = 1.3753

    log x = log 5.25 + log 23.73
    = .7202 + 1.3753
    = 2.0955

    then x = 10^2.0955
    = 10^2 * 10^.0955

    now go to the "antilog" table and find .0955

    here is one such antilog table:
    cdn1.byjus.com/wp-content/uploads/2019/07/Antilog-Table-Image.png

    I would find .09 in the first column, then in that row across the top to 5
    that would give me 1245. That takes care of the .095 but we had .0955
    While still in the row for .09 go to the difference section of the table and find
    the 5 at the top, I see a 2 , so we add that to 1245 to get 1247,
    really 1.247

    It was assumed that there was a decimal place after the first digit
    and that's where the 10^2 comes in
    so we multiply 1.245 by 10^2 to get 124.5

    actual answer after 7 seconds on my calculator
    5.25 * 23.72 = 124.5825
    notice that my log table method was off by 1 decimal, that's major.

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  4. How can I snapp my solving

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