5 What is the Zscore associated with the following Z025 Z056

5. What is the Z-score associated with the following: Z0.25 Z0.56 Z0.72

Solution

Z0.10
look in the standard normal distribution and search for value 1-0.10 = 0.90, closest value is 0.8997 which lies in row 1.20 and column 0.08 so 1.20+0.08 = 1.28
required Z-score = 1.28

Z0.25
Z-score is 0.67

Z0.56 = - Z(1-0.56) = - Z0.44
Z-score is -0.15

Z0.72 = - Z(1-0.72) = - Z0.28
Z-score is -0.58