A study found that, in 2005, 12.5% of U.S. workers belonged to unions (The Wall Street Journal, January 21, 2006). Suppose a sample of 380 U.S. workers is collected in 2006 to determine whether union efforts to organize have increased union membership.
1. Formulate the hypotheses that can be used to determine whether the data are (or are not) convincing evidence that union membership exceeded 12.5% in 2006 (it has increased in 2006).
H0: p
Ha: p
2. If the sample results show that 50 of the workers belonged to unions, what is the sample proportion of workers belonging to unions (to 3 decimals)?
Complete the following, assuming an ? level of .05.
3. Compute the value of the test statistic (to 3 decimals).
4. What is the p-value (to 3 decimals)?