Question 1192875
the first is z between (14.75-15.85)/9.5/sqrt(12)=-0.401 and (22.5-15.85)/9.5/sqrt(12)=2.74 That probability is 0.6527
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That is z< (11.25-15.85)/9.5/sqrt(12)=-4.60*sqrt(12)/9.5=-1.68
probability is 0.0465