# Statistics 250

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What is the probability of randomly selecting a z-score less than z = –0.80 from a normal distribution.
a)-0.2119
b)0.7881
c)0.2119
d)-0.7881

• Statistics 250 -

This can be done without even looking at any tables, assuming the correct answer is in there
First of all, rule out the two negative results, prob's can't be negative
a z score of 0 would be .5
any negative z-score would be < .5
So there is only one choice, namely C) .2119

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