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Math Help - need small help with finding area...confused.

  1. #1
    Newbie Almondzqueen's Avatar
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    need small help with finding area...confused.

    So i am asked to find the area under the standard normal curve to the right of z=-1.25......(i look up my chart, it says .1056, so I subtract 1-. 1056= .8944)
    Is this .8944 correct?

    Then the second part asks me to findthe area under the standard normal cruve to the LEFT of z=1.25.
    I think it is now .1056!


    Can someone enlighten me and help to check these over? Thank you!
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  2. #2
    Member
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    Its really helpful to draw the graph of the distribution, and write the z values and shade the area in

    So area to the right of z=-1.25 is
    P(Z>-1.25)=0.5+(0.5-P(Z>1.25)=1-.1056=0.8944 by symmetry
    So similiarly the area to left of 1.25 is
    P(Z<1.25)=0.5+(0.5-P(Z>1.25)=1-.1056=0.8944
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  3. #3
    Newbie Almondzqueen's Avatar
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    California
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    thanks

    ok, thats what I formally thought. Thanks so much for clarifying this.
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