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Students should spend average of 12 hours studying. Survey done on 25 students and the distribution of total study hours per week is bell-shaped with a
68% of students spend between ? hours and ? hours on stats each week
95% of students spend between ? hours and ? hours on stats each week.
99.7% of students spend between ? hours and ? hours on stats each week.
The provided information are:
According to the empirical rule:
Approximately 68% of the data values fall within one standard deviation of mean.
Approximately 95% of the data values fall within two standard deviations of mean.
Approximately 99.7% of the data values fall within three standard deviations of mean.
(a)
It is known that 68% of the data lies within one standard deviations of the mean.
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