The histogram of the number of hours of sleep Stat 100 students reported getting each night roughly follows the normal curve with anaverage of 6.9 hours and a SD of 1.2 hours.

a.Approximately68%of the students sleep between_____hoursand_____ hours. (Put the smaller number first)

b.Approximately95%of the students sleep between_____hoursand_____hours. (Put the smaller number first)

c.If a student sleeps 4.8 hours per night what percent of the people sleepmorethan her? Do the problem in steps:

i.First, find the Z score=

ii.Shade the region representing the percent of people who sleep more than her:

Shade the region under the normal curve to the

left of the red vertical line or right of the red vertical line?

iii.So______% of studentssleep morethan her.

d.Whatpercentile is she in?(use your result from part c)

________th percentile

e.If a student is in the 85th percentile how much does she sleep? Fill in the 3 blanks below.

i.85th percentile corresponds to middle area =_______ %.

ii.The correspondingZ score=________

iii.She sleeps_________hours. (Give hours to 2 decimal places.)

f.If a student is in the 15th percentile, how much does she sleep? (Hint: Use part e)hours. (Give answer to 2 decimal places.)