An issue with legalization of medical marijuana is "diversion", the process in which medical marijuana prescribed for one person is given, traded, or sold to someone who is not registered for medical marijuana use. The mean number of days that

105

adolescents in substance abuse treatment used medical marijuana in the last six months was

98.66.

Assume the population standard deviation is

32

days. Complete parts (a) through (d) below.

a. Find a

99%

confidence interval for the mean number of days,

,

of diverted medical marijuana use in the last 6 months of all adolescents in substance abuse treatment.

The

99%

confidence interval for

is from

enter your response here

days to

enter your response here

days.

(Round to two decimal places as needed.)

b. Find a

90%

confidence interval for the mean number of days,

,

of diverted medical marijuana use in the last 6 months of all adolescents in substance abuse treatment.

The

90%

confidence interval for

is from

enter your response here

days to

enter your response here

days.

(Round to two decimal places as needed.)

c. Draw a graph to display both confidence intervals. Choose the correct graph below.

A.

90110

99%CI

for

90%CI

for

A number line has a horizontal axis labeled from 90 to 110 in increments of 1. An interval labeled "99% C I for mu" extends from 90.6 to 106.8. An interval labeled "90% C I for mu" extends from 92.6 to 104.8. All values are approximate.

B.

90110

99%CI

for

90%CI

for

A number line has a horizontal axis labeled from 90 to 110 in increments of 1. An interval labeled "99% C I for mu" extends from 90.6 to 106.8. An interval labeled "90% C I for mu" extends from 93.6 to 103.8. All values are approximate.

C.

90110

90%CI

for

99%CI

for

A number line has a horizontal axis labeled from 90 to 110 in increments of 1. An interval labeled "90% C I for mu" extends from 90.6 to 106.8. An interval labeled "99% C I for mu" extends from 93.6 to 103.8. All values are approximate.

D.

90110

99%CI

for

90%CI

for

A number line has a horizontal axis labeled from 90 to 110 in increments of 1. An interval labeled "99% C I for mu" extends from 92.6 to 104.8. An interval labeled "90% C I for mu" extends from 93.6 to 103.8. All values are approximate.

d. Which confidence interval yields a more accurate estimate of

?

Explain your answer.

The

90%

99%

confidence interval is a more accurate estimate, because it is

narrower

wider

than the

99%

90%

confidence interval.