Question

The publisher of Celebrity Living claims that the mean sales for personality magazines that feature people such as Megan Fox or Jennifer Lawrence are 1.5 million copies per week. A sample of 10 comparable titles shows a mean weekly sales last week of 1.3 million copies with a standard deviation of 0.9 million copies.

Answer 1

Answer and Explanation:

The computation is shown below:

For determining each part first we have to do the following calculations

Critical value of t = 3.250

Null hypothesis = 1.5

Alternative hypothesis ≠ 1.5

Population mean $\mu$ = 1.5

Sample mean $\bar X$= 1.30

Sample size $n$ = 10.00

Sample standard deviation $s$ = 0.900

Standard error of mean is

$s_x = \frac{s}{\sqrt{n} }$

$= \frac{0.900}{\sqrt{10.00}}$

= 0.2846

Test static is

$t = \frac{x - \mu}{s_x}$

$= \frac{1.30 - 1.5}{0.2846}$

= -0.703

a. The null hypothesis is

μ = 1.5

Alternate Hypothesis is

μ ≠ 1.5

b. reject $H_o$ if t is not between

-3.250 and 3.250

c. The value of the test statistic is

t = -0.703

(as we have computed above)

d. fail to reject $H_o$ as this data does not contradict the publisher claim