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    Help !



    I finished the rest of my homework but this one question is frustrating me and I can't figure it out. someone help please.

    The weekly food cost for a family of 4 is normally distributed with a mean $158.29 and a standard deviation of $31.48. What are the low and high weekly food costs for the middle 60% of families from this distribution?

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    Quote Originally Posted by scastillo924 View Post
    I finished the rest of my homework but this one question is frustrating me and I can't figure it out. someone help please.

    The weekly food cost for a family of 4 is normally distributed with a mean $158.29 and a standard deviation of $31.48. What are the low and high weekly food costs for the middle 60% of families from this distribution?
    What are the Z-Scores that capture (or enclose) the middle 60% of the standard normal distribution?

    Once you've determined this, then use the linear transformation:

    Low =(-Z)*std + mean

    High = (Z)*std + mean

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    got the answer ! thanks !

    low= -.84(31.48) + 158.29= 184.73
    high= .84(31.48) +158.29=131.84

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    Quote Originally Posted by scastillo924 View Post
    got the answer ! thanks !

    low= -.84(31.48) + 158.29= 184.73
    high= .84(31.48) +158.29=131.84
    Really?...How did you obtain Z-Scores of +-.84?

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