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Two well-known aviation training schools are being compared using random samples of their graduates. It is found that 70 of 140 graduates of Fly-More Academy passed their FAA exams on the first try, compared with 104 of 260 graduates of Blue Yonder Institute.

a. To compare the pass rates, what would be the pooled proportion?

b. What is the test statistic?

c. Find the critical value for a right-tailed test at ? = .05.

d. Find the p-value.

d. What is your decision regarding the null hypothesis?

User Kungfooman
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2 Answers

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Final answer:

To compare the pass rates, calculate the pooled proportion and the test statistic. Find the critical value for a right-tailed test at α = 0.05. The p-value is smaller than 0.05, so we reject the null hypothesis that the pass rates are the same.

Step-by-step explanation:

a. To compare the pass rates, we can calculate the pooled proportion by adding the number of successful graduates from both schools and dividing by the total number of graduates. For Fly-More Academy, the pass rate is 70/140 = 0.5, and for Blue Yonder Institute, the pass rate is 104/260 = 0.4. The pooled proportion is (70+104)/(140+260) = 0.433.

b. The test statistic for comparing two proportions is calculated using the formula: test statistic = (p₁ - p₂) / √(pooled proportion * (1 - pooled proportion) * ((1/n₁) + (1/n₂))). Using the values from the question, the test statistic is (0.5 - 0.4) / √(0.433 * (1 - 0.433) * ((1/140) + (1/260))) = 2.29.

c. The critical value for a right-tailed test at α = 0.05 can be found using a normal distribution table or a statistical software. For a significance level of 0.05, the critical value is approximately 1.645.

d. The p-value is the probability of obtaining a test statistic as extreme as the one calculated, assuming the null hypothesis is true. To find the p-value, we can use a statistical software or a t-distribution table. In this case, the p-value is smaller than 0.05, indicating strong evidence against the null hypothesis.

e. Based on the p-value being smaller than the significance level of 0.05, we reject the null hypothesis. This means that there is evidence to support the claim that the pass rates of the two aviation training schools are different.

User Erv Walter
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3 votes

Answer:

Step-by-step explanation:

Given that two well-known aviation training schools are being compared using random samples of their graduates

Fly more academy 70 of 140

Blue Yonder 104 of 260

Combined pass = (70+104) out of (140+260)

a) Pooled proportion=
(174)/(400) \\=0.435

b) H0: p1 = p2

Ha: p1 ≠p2

(two tailed test)

p difference=
(70)/(140) -(104)/(260) =0.10

std error for difference (using pooled proportion) =
\sqrt{(0.435*0.565)/(400) } \\=0.0248

Test statistic = p difff/std error = 4.034

c) Critical value for 0.05 is 1.96

d) p value is < 0.005

Since p < 0.05 our significant level we reject H0

There is significant difference between the two proportions.

User Hcaelxxam
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