Question 1170299
z=(x-mean)/sd
so a is z=-0.25/0.2 or 1.25 sd
z <1.25 with probability of 0.1056 or 10.56%
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this is between -1.5 sd and 0.25 sd.
probability is 0.5319 or 53.19%
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this would be z>2.5 with probability of 0.0062