Formula Sheet BSTA 300Final Comprehensive Exam Organization of DataSolution Correct Answer KeyQuestion 1In a market study for Target, a researcher found that 70% of customers are repeat customers. If 14 customers areselected atrandom, find the probability of getting.P = 0.7, q =1–p = 0.3n = 141.Exactly 9 of them are repeat customersP(X=9) =ଵସ!ହ!ଽ!* (0.7)9(0.3)0.3=0.1962.At least 11 of them are repeat customersP(X>=11) = P(X=11) + P(X=12) + P(X=13) + P(X=14)=0.3553.At most 12 of them are repeat customersP(X<=12) = P(X=0) + P(X=1) + P(X=2) + …..+ P(X=12)= 0.839Question 2Using computer software (Excel, or calculation website) find the following probabilities and z values to 5 decimalplaces1. P(z< .12345)=0.54912. Find z0 such that P(z>z0)=0.12345z0 = 1.158Question 3Scores are obtained from the Law School Admission Test (LSAT) are normally distributed with a mean score of 650and a standard deviation of 120.Mean = 650, SD = 1201.If a test score is selected at random, find the probability that it is less than 700.z = (700–650)/120 = 0.4167P(X<700) = P(z<0.4167) =0.6616Preview Mode
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