Question 345979
P(Bad)=4/120=1/30
P(Good)=29/30
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P(all 4 Good)=P(Good)*P(Good)*P(Good)*P(Good)
P(4G)={{{(29/30)^4=707281/810000=0.873}}}
P(not 4G)={{{1-0.873=0.127}}}
The probability of rejection is then {{{P=0.127}}}.