Question

A. State the null hypothesis (𝐻𝑜) and the alternative hypothesis (𝐻𝑎) for each

of the following. (10 points)

1. A medical trial is conducted to test whether or not a new medicine reduces

cholesterol by 25%.

𝐻𝑜:

𝐻𝑎:

2. We want to test whether the mean GPA of students in a certain college is different

from 2.0 (out of 4.0).

3. We want to test if college students take less than five years to graduate from

college, on the average.

𝐻𝑜:

𝐻𝑎:

4. On a state driver’s test, about 40% pass the test on the first try. We want to test if

more than 40% pass on the first try.

𝐻𝑜:

𝐻𝑎:

5. A research on whether computer aided instruction is better than lecture method

of a lesson presentation.

𝐻𝑜:

𝐻𝑎:

Answer 1

1)

H₀ : The drug reduces cholesterol by 25%. p = 0.25

H_a : The drug does not reduce cholesterol by 25%. p ≠ 0.25

2)

H₀ : $\mu=2.0$

H_a : $\mu\not=2.0$

3)

H₀: μ ≥ 5

H_a: μ < 5

4)

H₀: p = 0.40

H_a: p > 0.40

5)

H₀: Computer aided instruction is not better than lecture method of lesson presentation.

H_a:  Computer aided instruction is better than lecture method of lesson presentation.