Chapter 5 - Continuous Random Variables - Exercises 5.73 - 5.92 - Learning the Mechanics - Page 256: 5.79c

$P(x\geq38)=.6950$

$q=1-p=1-.40=.60$ $\mu=np=100(.40)=40$ $\sigma=\sqrt {npq}=\sqrt {100(.40)(.60)}=4.90$ $\frac{(37+.5)-40}{4.90}=-.51$ $P(x\geq38)=1-P(x\leq37)=1-P(z\leq-.51)=P(z\geq0)+P(-.92\leq z\leq0)=P(z\geq0)+P(0\leq z\leq.51)=.5+.1950=.6950$