against Ha: 0.50, each with n = 400. Jonesgets = 220~400 = 0.550. Smithgets

against Ha: π ≠ 0.50, each with n = 400. Jonesgets ˆπ = 220~400 = 0.550. Smithgets ˆπ = 219~400 = 0.5475.

(a) Showthatthe P-valueis0.046forJonesand0.057forSmith.Using α = 0.05, indicatein eachcasewhethertheresultis“statisticallysignificant.”Usingthis,explainthemisleading aspectofreportingthetestresultas“P-value ≤ 0.05” versus“P-value > 0.05,” oras“reject H0” versus“Donotreject H0”, withoutreportingthe P-value.

(b) Useconfidenceintervalstoshowthat,inpracticalterms,thetwostudieshadverysimilar results.