Appendix

# Tables for Reference

This appendix includes tables for finding probabilities and/or critical values for the three distributions used in this book: the *Z*-distribution (standard normal), the *t*-distribution, and the binomial distribution.

## The Z-Table

Table A-1 shows less-than-or-equal-to probabilities for the *Z*-distribution; that is, *p*(*Z* ≤ *z*) for a given *z*-value. (See Chapter 10 for calculating *z*-values for a normal distribution; see Chapter 12 for calculating *z*-values for a sampling distribution.) To use Table A-1, do the following:

**Determine the***z*-value for your particular problem.The

*z*-value should have one leading digit before the decimal point (positive, negative, or zero) and two digits after the decimal point; for example,*z*= 1.28, –2.69, or 0.13.**Find the row of the table corresponding to the leading digit and first digit after the decimal point.**For example, if your

*z*-value is 1.28, look in the “1.2” row; if*z*= –1.28, look in the “–1.2” row.**Find the column corresponding to the second digit after the decimal point.**For example, if your

*z*-value is 1.28 or –1.28, look in the “0.08” column.**Intersect the row and column from Steps 2 and 3.**This number is the probability that

*Z*is less than or equal to your*z*-value. In other words, you’ve found*p*(*Z*≤*z*). For example, if*z*= 1.28, you see*p*(*Z*≤ 1.28) = 0.8997. For*z*= –1.28, you see*p*(*Z*≤ –1.28) = 0.1003.

Table A-1 The *Z*-Table

## The t-Table

Table A-2 shows right-tail probabilities for selected ...

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