Chapter 5 - Continuous Random Variables - Exercises 5.20 - 5.52 - Learning the Mechanics - Page 242: 5.34d

$p(92\leq x\leq 116)=.8185$

$z_0=\frac{x-\mu}{\sigma}=\frac{92-100}{8}=-1$ $z_0=\frac{x-\mu}{\sigma}=\frac{116-100}{8}=2$ According to table IV, page 773: $p(0\lt z\lt 1)=.3413$ $p(0\lt z\lt 2)=.4772$ $p(92\leq x\leq 116)=p(-1\leq z\leq 2)=p(-1\leq z\lt0)+p(0\leq z\leq2)=p(0\lt z\leq1)+p(0\leq z\leq2)=.3413+.4772=.8185$