statistics

Please help. I have no idea what I am doing

Use the standard normal (z score) table to find: P(-1.00 ≤ z)

&
Find the probability that a data value picked at random from a normal population will have a standard score (z) that lies between the following pairs of z-values.
z = 0 to z = 2.10

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  1. -1.00 ≤ z is the same as z ≥ -1
    or
    1 - P(z ≤ -1.00) ----> .8413

    I don't know how old your tables are or what they look like, but for most of them ...
    here is a typical one:
    http://www.stat.ufl.edu/~athienit/Tables/Ztable.pdf
    find -1.0 in the horizontal under the 00 vertical to get . 1587
    so
    1 - P(z ≤ -1.00)
    = 1 - .1587 = .8413

    Of course with internet access, the use of tables is obsolete and we use on-line applets like this one:
    http://davidmlane.com/normal.html

    since you want the values above a z-score of -1
    leave the mean at 0
    and the SD at 1
    click on "above" and enter -1
    read .8413 in the answer window.

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