Answer:
a) H₀ : p = 0.5
b) z = 2.0785
c) p - value = 0.0188
d) Our conclusion is that there has been a significant increase in the proportion of registered voters who are planning to vote for the incumbent president
Explanation:
Probability of those planning to vote for the incumbent president before the debate, P₀ = 50/100 = 0.5
a) The null and the alternative hypothesis
Let the null hypothesis be represented by
and the alternative hypothesis be represented by
H₀ : p = 0.5
b) compute the test statistics
sample size, n = 1200
number of voters planning to vote for the incumbent president, x = 636
Probability of those planning to vote for the incumbent president in the selected sample:
Formula for the test statistic:
z = 2.0785
c)
For , the critical value as checked from the normal table will be:
The P value for z > 2.0785
d) What do you conclude?
since , we will reject the null hypothesis.
Our conclusion is that there has been a significant increase in the proportion of registered voters who are planning to vote for the incumbent president