in a given year, the rate of flu infection for the general public was 8.3%. And sample of 200 people who receive the flu vaccine, the rate of flu infection was just 3.5%. What conclusion should you draw?

Step-by-step explanation:

Step 1: Define significance level

In this hypothesis testing problem, significance levels α is selected: , the associated z-value from Laplace table:

Φ() = α -

=> =

Step 2: Define null hypothesis () and alternative hypothesis ()

: rate of flu infection = 8.3% or 8.3/100 = 0.083

: rate of flu infection < 8.3% or 8.3/100 = 0.083

Step 3: Apply the formula to check test statistic:

with is actual sampling percent, is rate of flu infection of , is number of samples.

The null hypothesis will be rejected if

Step 4: Calculate the value of K and compare with

We have

=>This is good evidence to reject null hypothesis.

=> The actual rate is lower. (As states)

Hope this helps!

:)