Ask Me Help Desk

Ask Me Help Desk (https://www.askmehelpdesk.com/forum.php)
-   Mathematics (https://www.askmehelpdesk.com/forumdisplay.php?f=199)
-   -   How do you do scientific notation? (https://www.askmehelpdesk.com/showthread.php?t=301821)

  • Jan 10, 2009, 03:35 PM
    shortandsmall
    how do you do scientific notation?
    how do you do scientific notion?can you do this problem as a prctice problem and explin step by step?
    thanks so much=]

    here's the problem:

    0.000758
  • Jan 10, 2009, 03:58 PM
    Capuchin

    Okay, I will do a similar problem all the way through, and then you can apply the same principles to your problem so I can make sure you've understood it. OK?

    I'll take a number similar to yours.

    Write 0.00004637 in scientific notation.

    Okay, so we first need to understand what scientific notation is. Essentially it's a number of the form .

    we can rewrite our current number in the form .

    Do you see why this is? is simply 1, so we can multiply it by that and still have the same number.

    Now we have some fun.

    Every time you divide by 10 (which means moving the decimal point one place to the left), we add 1 to y. Every time we multiply by 10 (move the decimal point to the right), we take 1 from y.

    so to get from to , we have to move the decimal point 5 places to the right. This means that we take 5 from y.

    So our final answer is .

    Now, we can get the original number back (to check), by actually doing the calculation.

    , so we can see that this is correct.

    Now you have a go with your question.
  • Jan 10, 2009, 04:14 PM
    kitkat2000
    0.000758
    you need to start with a number between 1-10 so place a decimal point between the 7&5. the number should look like this 0.0007.58. Count the number of digits between the original decimal point and the one you just made, which is 4. the answer is 7.58x10 to the -4th power. The negative indicates that the number has a decimal point. The -4 should be written in the top right corner of the 10
  • Jan 10, 2009, 05:10 PM
    KISS

    0.000758

    I'll do it a different way:

    Engineering notation means that the first number is between 1 and 999. So, lets move the decimal by 3. 758 E-6. E is another way of writing 10^(-6).

    To get 758 E-3 into scientific notation, lets move the decimal place by 2 or 7.58 E-4.

    If we take 0.0007.58

    Note I wrote the number with 2 decimals on purpose. If we count to the left 4 times from the 7.58 decimal, we have the new decimal place.

    Multiplying 0.000758 by (10^1) makes the number .00758 E-1
    Do it again: 0.0758 E-2, again 0.758 E-3; and again 7.58 E -4

    The E-4 means you take 7.58 and multiply by 10^(-4) or 0.0001
    Thus 7.58 * 0.0001 equals 0.000758

  • All times are GMT -7. The time now is 10:25 AM.