Explore BrainMass

Explore BrainMass

    Calculating mean, standard deviation and z-score

    This content was COPIED from BrainMass.com - View the original, and get the already-completed solution here!

    Please help with the following statistics problem. Provide step by step calculations for each.

    You learned that 27% of all small business owned by non-Hispanic whites nationwide are women-owned firms. In a random sample of 350 small businesses owned by non-Hispanic whites, let x be the number that are owned by a woman.

    a) Find the mean of x.

    b) Find the standard deviation of x.

    c) Find the z-score for the value x= 99.5.

    d) Find the approximate probability that the number of small businesses in the sample of 350 that are owned by a woman is 100 or more.

    © BrainMass Inc. brainmass.com June 4, 2020, 1:04 am ad1c9bdddf
    https://brainmass.com/statistics/z-test/calculating-mean-standard-deviation-z-score-377529

    Solution Preview

    a) Find the mean of x.

    p=probability that small business owned by non-hispanic whiles is woman=0.27
    n=350
    Mean=np=350*.27=94.5

    b) Find the standard deviation of x.
    Variance=np(1-p)=350*0.27*(1-0.27)= ...

    Solution Summary

    The following posting helps with calculations involving hypothesis testing. This solution describes the steps to find out mean, standard deviation and z-score in the given case. Step by step calculations are given for each problem.

    $2.19

    ADVERTISEMENT