step 1)
Ho : µ = 7.8
Ha : µ > 7.8
(Right tail test)
step2 )
Level of Significance , α = 0.05
critical t value, t* =
1.714 [Excel formula =t.inv(α/no. of tails,df) ]
reject Ho, if test stat > 1.714
step 3)
sample std dev , s = 0.270
Sample Size , n = 24
Sample Mean, x̅ = 7.900
degree of freedom= DF=n-1= 23
Standard Error , SE = s/√n = 0.270 / √
24 = 0.055
t-test statistic= (x̅ - µ )/SE = ( 7.90
- 7.8 ) / 0.055
= 1.814
step 4)
Decision; since, test stat = 1.814> 1.714 , reject HO
step 5)
Conclusion: There is enough evidence to conclude that teens sleep more than 7.8 hours on sundays at α=0.05
6) The average amount of sleep a teen gets on Sundays is 7.8 hours. A researcner reeis unat ume average time is greater than 7.8 hours. The researcher collects data from 24 teens in a particular...