SOLUTION: Solve completely. Follow the procedure below: A. Setup the null and alternate hypothesis B. What is the level of significance “a” (alpha)? What test will you use and how ma

Click here to see ALL problems on Probability-and-statistics

Question 1175856: Solve completely. Follow the procedure below:
A. Setup the null and alternate hypothesis
B. What is the level of significance “a” (alpha)? What test will you use and how many tails is it?
C. Find the Critical Value given the level of significance and the number of tails (and the given n if it is a t-test). Draw a
bell curve.
D. Write the Decision Rule given the Critical Value. Note: A two-tailed test will have a positive and a negative Critical Value.
E. Solve for the test statistic (z or t-test). Compare with the Critical Value.
F. Conclusion: Reject or Do Not Reject? Explain in terms of the decision rule.
z-test

3. A cheerleading squad received a mean rating (out of 100 possible points) of 75 with a standard deviation of 7 in competitions over the previous three seasons. The same cheerleading squad performed in 36 local competitions this season with a mean rating equal to 78 in competitions. Determine whether mean ratings increased this season (compared to the previous three seasons) at a .04 level of significance.
Answer by ewatrrr(24785) (Show Source):
You can put this solution on YOUR website!

Hi Previous 3 seasons: μ = 75 and σ = 7 Sample: n = 100 and x̄ = 78 (out of 100) Ho: μ = 75 Ha μ > 75 1)Level of significance is .04 2) One-tailed, critical value = invNorm(.96) = 1.7507 3) Sample > 30, population σ known: use z-test 4) z = 3/(7/10) = 4.2857 z > critical value Reject Ho. Evidence shows an increase in mean ratings this season. Wish You the Best in your Studies.