In: Statistics and Probability
Flu cases this past flu season in the remulak school system n=500 were 15 per week. for the entire state, the weekly average was 16, and the standard deviation was 15.1. are the kids in remulak as sick as the kids throughout the state.
Given
μ = 16 Population Mean
σ= 15.1 Population Standard
Deviation
X̅ = 15 Sample Mean
n =500 Sample Size
Let α = 0.05 Level of
significance
Since the population standard deviation is known, we use the
z-test
The null and alternative hypothesis
are
Ho : μ = 16
H1 : μ ≠ 16 … (Since we have to test if the kids in remulak as sick
as the kids throughout the
state.)
Find Calculated Value of test statistic
z
Test statistic z-calc =
-1.4808
This is a double sided
z-test
p-value for the test is found using Excel function
NORM.S.DIST
p-value = 2 * NORM.S.DIST(-1.4808,
TRUE)
p-value = 0.1387
Since 0.1387 >
0.05
that is p-value >
α
we DO NOT reject Ho
Conclusion
The kids in remulak are as sick as the kids throughout the
state.