Answer:
We have 96% of confidence that the true proportion of people who responded that they have a plan to buy one electric car is between (0.121 and 0.303).
Step-by-step explanation:
For this case the estimated proportion of people who responded that they have a plan to buy one electric car is given by:
Where X represent the number of people who responded that they have a plan to buy one and n represent the sample size selected
We know that the confidence level for this case is 96% of confidence, then our significance level would be and
. And the critical value would be:
The confidence interval for the true proportion is given by this expression:
Replacing the data given we got:
We have 96% of confidence that the true proportion of people who responded that they have a plan to buy one electric car is between (0.121 and 0.303).