Suppose that the amount of time that students spend studying in the library in one sitting is normally distributed with mean 43 minutes and standard deviation 20 minutes. A researcher observed 49 students who entered the library to study. Round all answers to 4 decimal places where possible. a. What is the distribution of X? X - N( 43 20 b. What is the distribution of x? ¤ - N( 43 2.8571 v) o c. What is the distribution of æ? x - N( 2107 d. If one randomly selected student is timed, find the probability that this student's time will be 140 between 44 and 47 minutes. .0593 e. For the 49 students, find the probability that their average time studying is between 44 and 47 minutes. .2824 f. Find the probability that the randomly selected 49 students will have a total study time more than 2156 minutes. .3632 g. For part e) and f), is the assumption of normal necessary? NoO Yes o h. The top 20% of the total study time for groups of 49 students will be given a sticker that says "Great dedication". What is the least total time that a group can study and still receive a sticker? minutes

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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.