Question

The following n = 10 observations are a sample from a normal population. 7.3 7.1 6.5 7.4 7.6 6.3 6.9 7.7 6.4 6.9 (a) Find the mean and standard deviation of these data. (Round your standard deviation to four decimal places.) mean standard deviation (b) Find a 99% upper one-sided confidence bound for the population mean μ. (Round your answer to three decimal places.) (c) Test H0: μ = 7.5 versus Ha: μ < 7.5. Use α = 0.01. State the test statistic. (Round your answer to three decimal places.) t = State the rejection region. (If the test is one-tailed, enter NONE for the unused region. Round your answers to three decimal places.) t > t

Answer 1

a)

from above

sample mean =7.01

standard deviation =0.4977

b)

for 99% upper CI; and 9 df, critical t=		2.821
margin of error E=t*std error                            =		0.444

Upper bound=sample mean+E=

7.454

c)

sample size             n=	10
sample std deviation s=	0.498
std error sx=s/√n=	0.1574
test stat t='(x-μ)*√n/s=	-3.114

rejection region :

t> NONE

t< -2.821

reject null hypothesis