A journal published a study of the lifestyles of visually impaired students. Usingdiaries, the students kept track of severalvariables, including number of hours of sleep obtained in a typical day. These visually impaired students had a mean of 8.65

8.65 hours and a standard deviation of 2.14

2.14 hours. Assume that the distribution of the number of hours of sleep for this group of students is approximately normal. Complete parts a through c.

a. Find P(xgreater than

>12).

P(xgreater than

>12)equals

=

0.0582

0.0582 (Round to four decimal places asneeded.)

b. Find P(8less than

<10).

P(8less than

<10)equals

=

0.3532

0.3532 (Round to four decimal places asneeded.)

c. Find the value a for which P(xless than

=0.2

0.2.

nothing

(Round to two decimal places asneeded.)