Chapter 5 - Continuous Random Variables - Exercises 5.20 - 5.52 - Applying the Concepts - Basic - Page 243: 5.43c

$p(x\lt850)=.9066$

$z=\frac{x-\mu}{\sigma}=\frac{850-605}{185}=1.32$ According to table IV, page 773: $p(0\lt z\lt1.32)=.4066$ $p(x\lt850)=p(z\lt1.32)=p(z\lt0)+p(0\lt z\lt1.32)=p(z\lt0)+p(0\lt z\lt1.32)=.5+.4066=.9066$