Suppose that the amount of time that students spend studying in the library in one sitting is normally distributed with mean 47 minutes and standard deviation 17 minutes. A researcher observed 49 students who entered the library to study. Round all answers to 4 decimal places where possible.   1.If one randomly selected student is timed, find the probability that this student's time will be between 45 and 49 minutes 2.For the 49 students, find the probability that their average time studying is between 45 and 49 minutes. 3.The top 10% 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.