The lengths of lumber a machine cuts are normally distributed with a mean of 97 inches and a standard deviation of 0.4 inch. ​(a) What is the probability that a randomly selected board cut by the machine has a length greater than 97.12 ​inches? ​(b) A sample of 45 boards is randomly selected. What is the probability that their mean length is greater than 97.12 ​inches? ​(a) The probability is nothing. ​(Round to four decimal places as​ needed.) ​(b) The probability is nothing. ​(Round to four decimal places as​ needed.)

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Estimation

A new framework of data analysis where the new statistical methods are used for interpreting the results and analyzing the data is known as estimation in statistics.