Sorry, can't do graphing in Yahoo Answers.
Degrees of freedom = N1 + N2 - 2 = 18 + 12 - 2 = 28 d.f.
0.02 significance with 0.01 in each tail of the distribution since H1 is "NOT EQUAL"
So, critical regions are values greater than 0.01 or less than -0.01
e) Critical Values: t = 2.467 (from t-table using 28 d.f. and alpha equal to 0.02 two tail test.
f) Value of Test Statistic for sample:
First, calculate the "pooled" common variance since we are assuming both are coming from the same population. This formula will come right out of your textbook:
variance = [(18-1)(114.16^2) + (12-1)(97.23^2)] / [(18-1) + (12-1)] = 11627
std. dev. = sqrt(variance) = sqrt(11627) = 107.83
Now, the standard error equals:
(std. dev.) (sqrt (1/18 + 1/12) ] = 107.83 (.3727) = 40.18
Finally, we can calculate the t-statistic:
t-statistic = (538.82 - 525.23) / 40.18 = 0.388
You can look up this t-statistic in a t-table to find the p-value:
p-value = 0.738 which is significantly greater than 0.02/2 = 0.01. The p-value is NOT in the critical region.
g) Statistical Conclusion:
Since t-statistic is less than the critical value: 0.388 < 2.467, DO NOT REJECT the null hypothesis
h) Sentence/Headline/Non-technical Conclusion in WORDS:
Based upon the data, the means for women and men are not significantly different.
Hope that helped