Question 1174178
z=(x-mean)/sd/sqrt(n)
> = (975-1050/100/sqrt(10) or -75*sqrt(10)/100 or z>= -2.37
probability is 0.9911
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z < (550-535)/98 or < 15/98=0.15
that probability is 0.5596
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I assume the question means what is the probability that the mean enrollment of these 25 schools is > 600. 
This is z > (600-535)/98/sqrt(25) or z > 65/19.6 or > 3.32
that probability is 0.00045 or 0.0005.