Answer:
z = 0.33
Step-by-step explanation:
The test statistic z can be calculated as:
Where p' is the proportion of the sample and p is the value in H0. Additionally, σ is equal to:
Where n is the size of the sample.
In this case, we have a sample of 136 subjects, so n = 136 and taking into account H0, p = 0.42. So, replacing the values, we get:
Then, p' is the proportion of the sample, so it is equal to:
p' = 59/136 = 0.4338
Now, replacing p' = 0.4338, σ = 0.0423 and p = 0.42, we get that the test statistic is:
Therefore, the answer is:
z = 0.33