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In a random sample of 175 community college students, the mean number of hours spent studying per week is 13.7 hours and the standard deviation is 4 hours.

Assuming the distribution of the number of hours community college students study per week is normally distributed, approximately how many of the students in the sample study between 9.7 and 17.7 hours per week?

Respuesta :

dragon1524

Answer:

Approximately there are 119.47 students per week

Step-by-step explanation:

The # of students in the sample study between 9.7 and 17.7 hrs per week;

P (9.7 < x < 17.7) =  P ((9.7 - 13.7)/4 < 7 < (17.7-13.7)/4)

P (-4/4 < 7 < 4/4)

P (-1 < 7 < 1)

0.8413 - 0.1587

0.6827

Therefore the # of student = n P

175 * 0.6827

119.47