help medal and fan thanks help plz
The ages of students in a school are normally distributed with a mean of 15 years and a standard deviation of 2 years. Approximately what percent of the students are between 14 and 18 years old?

24.17%
62.47%
30.85%
93.32%

Question

help medal and fan thanks help plz
The ages of students in a school are normally distributed with a mean of 15 years and a standard deviation of 2 years. Approximately what percent of the students are between 14 and 18 years old?

 24.17%
 62.47%
 30.85%
 93.32%

michele_laino · Answer

hint:
you have to use the table of the "erf" function, with these limits:
(15-14)/2 = 0.5 standard deviations below the mean
(18-15)/2= 1.5 standard deviations above the mean

michele_laino · Answer

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