Introductory Biostatistics

Example 3.5 What is the probability of obtaining azvalue between 1.0 and
1.58? We have

Prð 1 : 0 aza 1 : 58 Þ¼Prð 0 aza 1 : 58 Þ
Prð 0 aza 1 : 0 Þ

¼ 0 : 4429 
 0 : 3413

¼ 0 : 1016

and this probability is shown in Figure 3.9.

Example 3.6 Find azvalue such that the probability of obtaining a largerz
value is only 0.10. We have

Prðzb?Þ¼ 0 : 10

and this is illustrated in Figure 3.10. Scanning the table in Appendix B, we find

Figure 3.7 Graphical display for Example 3.3.

Figure 3.8 Graphical display for Example 3.4.

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