Question

Suppose that the average weekly wage for mothers just off welfare in the United States is $300. A random sample of 60 welfare mothers is given an assertiveness training class. One year later their average earnings are $330 with s=$85. Do these data provide sufficient evidence at the 5% significance level to infer that assertiveness training is effective in helping welfare mothers negotiate better wages?

Answer 1

Answer:

Yes, data provide sufficient evidence . And the pvalue is less than 0.05

Explanation:

Solution:

The correct option is c. Yes, the p-value is less than .05

Explanation:

The null and alternative hypothesis is:

H0 μ = 300

H1 :μ> 300

The test statistic is:

1-40 40 2.73 330-300 - -2.73

p-value = P(t > 2.73)

Using the excel below function, we have:

=TDIST(2.73, 59, 1) = 0.0042

2.73 is the test statistic and 59 is the degrees of freedom and 1 stand for a one-tailed test

Therefore the p-value is:

p-value = P(t > 2.73) = 0.0042