A normal population has a mean of 18.6 and a standard deviation of 4. Refer to the table in Appendix B.1. a. Compute the z-value associated with 25.0. (Round the final answer to 2 decimal places.)

z =

b. What proportion of the population is between 18.6 and 25.0? (Round z-score computation to 2 decimal places and the final answer to 4 decimal places.)

Proportion=

c. What proportion of the population is less than 18.0? (Round z-score computation to 2 decimal places and the final answer to 4 decimal places.)

Proportion=

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