Question 1192872
z=(x-mean)/sd
z>(553-548.4)/28.1=0.1637
probability z > 0.1637 is 0.4350
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for 35 students, the mean of the sampling distribution is 548.4, no change.
the sd is original sd/sqrt(n)=4.75
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z now is 4.6/4.75=0.97
the probability now is 0.1664