section 7.1
Standardizing a normal sampling distribution for means, Fact 4 (p. 399).
Z=ˉx-μˉxσˉx=ˉx-μσ/√n
section 7.2
Standardizing a normal sampling distribution for proportions, Fact 8 (p. 419).
Z=ˆp-μˆpσˆp=ˆp-p√pq/n