Definitions Complement rule: P(A^(C))=P(not A)=1-P(A) Addition rule for disjoint or mutually exclusive events: P(A ∪ B)=P(A or B)=P(A)+P(B) Solution The probability P(0<= z<= 2) is given in the row with z=2.0 and in the column with .00 of the normal probability table in the appendix: P(0<= z<= 2)=0.4772 The standard normal distribution is symmetric about 0: P(-2<= z<= 2)=2P(0<= z<= 2)=2(0.4772)=0.9544