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**stewardt** a) find P(-.12<Z<.54)

Mr F says: = Pr(Z < 0.54) - Pr(Z < - 0.12) = Pr(Z < 0.54) - Pr(Z > 0.12) = Pr(Z < 0.54) - [1 - Pr(Z < 0.12)] = Pr(Z < 0.54) + Pr(Z < 0.12) - 1.

Now use your tables.

b)find P(z=0) Mr F says: You should know that since Z is a continuous random variable, Pr(Z = a) = 0.

c) find the z-score that seperates the bottom 40% frin the top 60%

Mr F says: Pr(Z < - z*) = 0.4 => Pr(Z > z*) = 0.4 => Pr(Z < z*) = 0.6. Get z* by using your tables in a reverse way. Hence get -z*.

D) find the z-scores for which 95 % of the distribution is between -z and z

Mr F says: Pr(Z > z) = 0.025 => Pr(Z < z) = 0.975. Get z by using your tables in a reverse way.

If you are able to help me I want to thank you in advance

If you can help me more on a one on one basis then tell me so

let me know how much you would charge to help me