Thestandard normal distributionhas a normal distribution with mean of zero and a standard deviation of one.

Scores in this distribution are called z-scores, and typically we use z instead of x when seeking probabilities.

Use Excel to find the following:

Round your results to four decimal places.

a.The probability that a score is less than 2.50,

P( z < 2.50 ) =

b.The probability that a score is more than -1.25,

P( z > -1.25 ) =