To get the area that lies between z=-1.5 and z=2.5 we proceed as follows; The probability associated with the z=-1.5 is P(-1.5)=0.668 The probability associated with the z=2.5 is P(2.5)=0.9938 Therefore; The area under the indicated z-scores will be: P(2.5)-P(-1.5) =0.9938-0.668 =0.3258