Question

Given the following situations, write A, if it is two-tailed, B if one-tailed (left-

tailed), and C if one-tailed (right-tailed). (10 points)

1. Research on processed foods lessens the life span of a person.

2. A government official claims that the dropout rate for local schools is 25%.

3. A civil engineer is trying to prove that his new method of laying blocks is more

effective than the traditional method.

4. A new stockbroker, named XYZ, claims that their brokerage fees are lower than

that of the current fee.

5. A government official claims that the dropout rate for local schools is 25%.

Answer 1

1.

$H_0: \mu\ge\mu_0$

$H_a: \mu<\mu_0$

B one-tailed (left-tailed)

2.

$H_0: \mu=\mu_0$

$H_a: \mu\not=\mu_0$

A two-tailed

3.

$H_0: \mu\le\mu_0$

$H_a: \mu>\mu_0$

C one-tailed (right-tailed)

4.

$H_0: \mu\ge\mu_0$

$H_a: \mu<\mu_0$

B one-tailed (left-tailed)

5.

$H_0: \mu=\mu_0$

$H_a: \mu\not=\mu_0$

A two-tailed